Rockwell updates its mineral resources and mineral reserves

VANCOUVER, May 31, 2011 /CNW/ --
Announces probable reserves at Saxendrift

Preliminary assessments of Wouterspan, Tirisano and Niewejaarskraal

VANCOUVER, May 31, 2011 /CNW/ - Rockwell Diamonds Inc. ('Rockwell' or
the 'Company') (TSX: RDI; JSE: RDI; OTCBB: RDIAF) is pleased to
announce the release of updated mineral resource estimates for its
alluvial diamond deposits on its properties in South Africa.

At the time that Rockwell was founded in 2006, the Company started
developing a proprietary resource management system which is directly
applicable to the specifics of alluvial diamond deposits. It is based
on the National Instrument 43-101 regulations for the statement of
mineral resources and reserves but refined to be specific to alluvial
deposits. The Company's system is a conservative and consistent method
of declaring its mineral resources and mineral reserves. The grades and
diamond values, which have been calculated using this methodology
during the last four years, have been shown to accurately reflect the
output of the mines. The results of these studies are summarized in the
tables attached to this release and further details are provided in the
Company's Annual Information Form and technical reports that have been
filed today.

Mark Bristow, Director and acting CEO, Rockwell explains that: 'we
embarked on this process when Rockwell first started as a diamond
company. The progress is such that today, for the first time, we have
stated an estimate of mineral reserves: probable reserves of 4.9
million cubic metres at Saxendrift. This is the culmination of a
pre-feasibility study conducted during 2009 and 2010.'

'Over the past five years, our resource base has grown from some 12.3
million cubic metres of Inferred Resources to the current 82.1 million
cubic metres of inferred resources, 35.1 million cubic metres of
indicated resource and 4.9 million cubic metres of probable reserves in
our latest NI 43-101 statements. We have achieved this through
extensive exploration of our existing projects as well as the purchase
of other high potential properties. We have conducted preliminary
economic assessments at our Wouterspan, Niewejaarskraal and Tirisano
projects, and are encouraged by the potential returns of these
properties.' adds Bristow.

The Company, which currently produces some 2,500 carats of large gem
quality diamonds per month has set itself the objective of growing its
production to 10,000 carats per month within five years. It has the
capacity to deliver this growth through organic means, based on its
significant resource base and is currently reviewing various options to
fund these capital investments.

Rockwell owns 14 prospecting rights comprising some 30,000 hectares of
alluvial diamond potential in South Africa. Holpan and Klipdam, which
are currently being consolidated into a single operation, are located
in the Northern Cape. Saxendrift is located in the Middle Orange River
in the Northern Cape Province. In addition, the Company is in the final
stages of acquiring and redeveloping the Tirisano mine, located in
Ventersdorp in the North West Province. The mine will come on stream in
the second half of fiscal 2012. Other significant deposits include
Wouterspan and Niewejaarskraal, which the Company plans to
re-commission within the next two years.

Rockwell's mineral resource statement is summarized below:

 ___________________________________________________________________
|ROCKWELL MINERAL RESERVES & RESOURCES                              |
|___________________________________________________________________|
|PROPERTY       |CATEGORY |VOLUME (m(3))|VOLUME (m(3)) |grade       |
|               |         |NOV 30 2010  |FEB 28 2011*  |(ct/100m(3))|
|_______________|_________|_____________|______________|____________|
|               |Probable*|4,859,900    |4,570,40000   |0.50        |
|Saxendrift/    |_________|_____________|______________|____________|
|Kwartelspan    |Indicated|1,774,600    |NC            |0.66        |
|               |_________|_____________|______________|____________|
|               |Inferred |5,986,000    |NC            |0.56        |
|_______________|_________|_____________|______________|____________|
|               |Indicated|2,091,200    |1,907,900     |            |
|Klipdam        |_________|_____________|______________|1.21        |
|               |Inferred |949,000      |NC            |            |
|_______________|_________|_____________|______________|____________|
|               |Indicated|517,800      |415,600       |            |
|Holpan         |_________|_____________|______________|0.95        |
|               |Inferred |527,000      |NC            |            |
|_______________|_________|_____________|______________|____________|
|               |Indicated|404,700      |NC            |            |
|Erf 404        |_________|_____________|______________|0.63        |
|               |Inferred |127,000      |NC            |            |
|_______________|_________|_____________|______________|____________|
|Rietputs       |Inferred |782,000      |736,000       |0.76        |
|_______________|_________|_____________|______________|____________|
|               |Indicated|5,025,500    |NC            |            |
|Wouterspan     |_________|_____________|______________|0.70        |
|               |Inferred |37,774,000   |NC            |            |
|_______________|_________|_____________|______________|____________|
|Niewejaarskraal|Inferred |20,630,000   |NC            |0.84        |
|_______________|_________|_____________|______________|____________|
|               |         |             |              |            |
|_______________|_________|_____________|______________|____________|
|               |Indicated|25,279,900   |NC            |            |
|Tirisano**     |_________|_____________|______________|2.37        |
|               |Inferred |15,334,000   |NC            |            |
|_______________|_________|_____________|______________|____________|

Estimates were done as at November 30, 2010. These have been reconciled
to February 28, 2011 by including material removed by trial mining and
bulk sampling during the fourth quarter (Dec 1-Feb 28). 

NC - denotes no change.  'Value' denotes the average value of the sales
of diamonds during sampling.

Mineral resources that are not mineral reserves do not have demonstrated
economic viability.

* The Saxendrift probable mineral reserves are exclusive from the
indicated mineral resources.

** Tirisano acquisition is not yet complete as the mining rights have
not yet been ceded to Rockwell.

Note that Rockwell also holds the the Zwemkuil Project, including the
Zwemkuil, Mooidraai and Holsloot properties, which was also reviewed
during the 2011 fiscal year.  Although a significant exploration target
exists, there has not been sufficient work done to estimate mineral
resources as this time.

Estimates were completed by Rockwell's Manager, Resources, G.A. Norton,
(Pr. Sci. Nat.), a qualified person who is not independent of the
Company and reviewed by T.R. Marshall, PhD, (Pr. Sci. Nat.). Dr
Marshall, a qualified person who is independent of the Company, is
responsible for the estimates and has reviewed and approved the
contents of this release.

Further details of the resource estimates and the studies described
below are provided in technical reports which are filed on the
Company's profile at www.sedar.com.

The following studies were done in South African Rand (ZAR) and US
dollars (USD), and used a conversion rate of 6.8 ZAR:1 USD.

Saxendrift Prefeasibility Study

The Saxendrift property is located on the south bank of the Orange River
in the Herbert district of the Northern Cape Province, some 50 km
southwest of Douglas and some 160 km from Kimberley.    Rockwell holds
a 74% interest in the property. The other 26% is held by the Company's
Black Economic Empowerment partner.

During 2009/2010 trial-mining was initiated on Saxendrift as part of a
study to determine what portion of the gravel resource could be
converted to a reserve.  Capital costs of plant and equipment have been
determined through formal quotations acquired from suppliers. 
Operational parameters and operating costs were determined both during
the bulk-sampling and trial-mining phases on Saxendrift, and from
Rockwell's experience on its other operations.  It is believed that the
detail and accuracy of this study is at a pre-feasibility level.

The mine plan involves continued mining on the Saxendrift A terrace
during 2011/2012 while detailed exploration is undertaken on the C
terrace. The preferred method of mining the alluvial gravels is
strip-mining in a shallow, opencast operation.  The diamondiferous
alluvial gravels are relatively thin, unconsolidated to
semi-consolidated, tabular bodies with generally less than 20 metres
overburden.  The upper 2-3 metres of the sequence is calcreted to
varying degrees - usually to laminar or hardpan levels.  As a result,
prior to excavation, the sample block needs to be blasted, which breaks
up the hard calcrete carapace without damaging diamonds, which is then
stripped off using hydraulic excavators.  In various areas of the
property varying depths of calcretisation has meant that some of the
upper gravel layers are also highly cemented. In order to mitigate
against this problem, prior to excavation, the gravels are ripped by a
bulldozer which effectively liberates the gravels (and the diamonds)
from the calcrete matrix.  The disaggregated material is then loaded by
excavator, onto articulated dump trucks (ADT's) and transported to the
screening plant where some 23% of the gravel is removed.

The processing plant, which was commissioned in late 2008, is comprised
of four scrubbers followed by four 18 ft rotary pan-plants and has a
design plant-throughput of 800 tonnes per hour.  With an expected
annual treatment of 1,800,000 cubic metres some 9,000 carats of
diamonds are expected to be recovered through a bank of ten FlowSort
machines and an electronic grease table, as well as final hand-sort in
a glove-box under secure conditions.

On the basis of the trial-mining on terrace A and subsequent
pre-feasibility study, probable reserves were estimated for the
Saxendrift Mine.  The life-of-mine, based on these reserves, at the
proposed rate of mining of 150,000 cubic metres per month is estimated
at 2.7 years.  Since the plant has been built no additional capital
expenditure has been budgeted for the outstanding life of mine. 
Operating costs have been budgeted at ZAR7.5M/month.  The net present
value (NPV) at a discount rate of 20% is USD9.8 million.

The key parameters and results from the mine study are tabulated below:

 ____________________________________________________________
|                      Key Parameters        |   Key Results |
|____________________________________________|_______________|
|Volume of gravel                            |   Cubic Metres|
|____________________________________________|_______________|
|                            Probable Reserve|      4,859,900|
|____________________________________________|_______________|
|Average Grade                               | 0.5 ct/100m(3)|
|____________________________________________|_______________|
|Average sales value (2011)                  |    USD2,029/ct|
|____________________________________________|_______________|
|Proposed monthly throughput                 |      150,000m3|
|____________________________________________|_______________|
|Proposed mine life (reserves only)          |            2.7|
|____________________________________________|_______________|
|Operating Costs  (2011)                     |     ZAR43/m(3)|
|____________________________________________|_______________|
|Mining Royalties                            |        0.5-7%*|
|____________________________________________|_______________|
|Capex required to bring mine into production|*ZAR 88,237,005|
|____________________________________________|_______________|
|Earthmoving fleet budget                    |            N/A|
|____________________________________________|_______________|
|Tax                                         |            28%|
|____________________________________________|_______________|
|NPV at discount values of:                  |               |
|____________________________________________|_______________|
|                         15% (reserves only)| ZAR 75,082,638|
|____________________________________________|_______________|
|                         20% (reserves only)| ZAR 65,480,170|
|____________________________________________|_______________|
|                         25% (reserves only)| ZAR 57,464,170|
|____________________________________________|_______________|

*Royalties vary according to the profitability of the mining company,
subject to a minimum rate of 0.5% and maximum rate 7.0% for diamonds.

Wouterspan Preliminary Assessment

The Wouterspan Property is located on the northern bank of the Orange
River, about 100 km west of Douglas in the Northern Cape Province,
South Africa.  It is across the river from the Saxendrift mine. 
Rockwell holds 75% interest in the property. The other 27% interest is
held by a Black Economic Empowerment partner.

Rockwell conducted bulk sampling and trial mining activities at
Wouterspan until November 2008 and has retained the property on care
and maintenance since that time. Since the geology is similar to the
adjacent Saxendrift mine.

A preliminary assessment of the project was done based on the indicated
and inferred mineral resources at 30 November 2010.  The diamond value
used in the statement is the average received for 5,500 carats of
diamonds sold from the adjacent Saxendrift mine (USD2,029 per carat)
during fiscal 2010.  The assessment is preliminary in nature, and
includes inferred mineral that are considered too speculative
geologically to have the economic considerations applied to them that
would enable them to be categorized as mineral reserves, and there is
no certainty that the preliminary assessment will be realized.

Wouterspan is located in the same area as Saxendrift, so the geology is
similar and similar mining methods are expected to be employed.
Excavation of the gravels is not planned to change from the standard
techniques applied on all of Rockwell's alluvial diamond mines -
excavation by hydraulic excavator followed by transport of gravel to
the plant site in  mine haul  trucks.

The proposed processing plant will be a high-volume, low-cost plant,
specifically designed to deal with the peculiarities of the gravels
being processed.  The plant will comprise 8 (or 12) 18' rotary pan
plants and trial-mining will investigate the efficiency of sending
selected size fractions to selected pans, namely 2-6mm, -6-12mm and
12-32mm.  This is expected to greatly improve the recovery
efficiencies of the pans. The plant is planned to be automated to the
extent that optimal production, along with minimal downtime and
maintenance, can be attained.

The mine plan has been developed in two phases - phase 1, comprising
plant throughput of 180,000 cubic metres per month, for a period of
some 24 months, followed by phase 2, to achieve at throughput at some
340,000 cubic metres per month.  The overall mine life is 10 years. The
net present value (NPV) at a discount rate of 20% is USD126.4 million.

Key parameters and results of the preliminary assessment are summarized
below:

 _____________________________________________________________
|Key Parameters                              |Key Results     |
|____________________________________________|________________|
|Volume of Gravel                            |    Cubic Meters|
|____________________________________________|________________|
|                         Indicated resources|       5,025,500|
|____________________________________________|________________|
|                          Inferred resources|      37,774,000|
|____________________________________________|________________|
|Average Grade                               |  0.7 ct/100m(3)|
|____________________________________________|________________|
|Average sales value                         |     USD2,029/ct|
|____________________________________________|________________|
|Proposed monthly throughput                 |    340,000 m(3)|
|____________________________________________|________________|
|Proposed mine life (indicated and inferred  |              10|
|resources)                                  |                |
|____________________________________________|________________|
|Operating Costs                             |      ZAR45/m(3)|
|____________________________________________|________________|
|Mining Royalties                            |      Variable *|
|____________________________________________|________________|
|Capex required to bring mine into production|  ZAR122,000,000|
|____________________________________________|________________|
|Tax                                         |             28%|
|____________________________________________|________________|
|IRR                                         |            135%|
|____________________________________________|________________|
|NPV at discount values of:                  |                |
|____________________________________________|________________|
|                                         15%|ZAR1,199,219,358|
|____________________________________________|________________|
|                                         20%|  ZAR885,000,000|
|____________________________________________|________________|
|                                         25%|  ZAR667,000,000|
|____________________________________________|________________|

*Royalties vary according to the profitability of the mining company,
subject to a minimum rate of 0.5% and maximum rate 7.0% for diamonds.

Niewejaarskraal Preliminary Assessment

The Niewejaarskraal project is located on the south bank of the Orange
River in the Herbert district of the Northern Cape Province, some 57 km
southwest of Douglas and some 170 km from Kimberley.  The property is a
past producer that was acquired by Rockwell in 2009. It is held 74% by
Rockwell and 26% by the Black Economic Empowerment partner.

During 2008, Rockwell reprocessed the drilling data from a prior
operator and re-estimated the resources.  Since no processing has taken
place on Niewejaarskraal in the period 2009-2010, the resource volume
and grade figures remain unchanged as at November 30, 2010.  However,
during FY2010, Rockwell sold 5,500 carats of diamonds from the
adjacent Saxendrift mine on the open market for USD2,029 per carat. 
Until a reasonable parcel of stones have been recovered from the
Niewejaarskraal mine and sold, this value will be accepted at an
Inferred resource classification level.

During 2009/2010 Rockwell has proceeded with plans to complete
trial-mining and other studies.  Niewejaarskraal is located in the same
area as Saxendrift and Wouterspan, so the geology is similar and
similar mining methods are expected to be employed

There is an existing processing plant on Niewejaarskraal, but it will
need to be completely re-furbished and upgraded prior to
re-commissioning. The current plan, given that Rockwell is currently in
the process of re-opening the Wouterspan and Tirisano mines, is for the
Niewejaarskraal mine to remain on care and maintenance for the period
to fiscal 2013.

The proposed new processing plant will be a high-volume, low-cost plant,
specifically designed to deal with the peculiarities of the gravels
being processed.  The plant will comprise 8 (or 12) 18' rotary pan
plants and trial-mining will investigate the efficiency of sending
selected size fractions to selected pans, namely 2-6mm, -6-12mm and
12-32mm. This is expected to greatly improve the recovery efficiencies
of the pans.  The plant is planned to be automated to the extent that
optimal production, with minimal downtime and maintenance can be
attained.  The mine plan has been developed to run at some 340,000
cubic metres per month.  Anticipated costs for re-commissioning the
mine in 2013 is ZAR130 million, with an anticipated ZAR3 million
budgeted for on-going capital expenditures.

A preliminary assessment was completed, at a proposed throughput of
340,000 cubic metres per month at full production, the preliminary
estimation of mine life is 6 years, based on the inferred mineral
resources currently outlined at Niewejaarskraal. The net present value
(NPV) at a discount rate of 20% is USD52.7 million.

This assessment is preliminary in nature, and includes inferred mineral
resources that are considered too speculative geologically to have the
economic considerations applied to them that would enable them to be
categorized as mineral reserves, and there is no certainty that the
preliminary assessment will be realized.

The key parameters and results are tabulated below:

 ____________________________________________________________
|Key Parameters                              |Key Results    |
|____________________________________________|_______________|
|Volume of gravel                            |   Cubic Metres|
|____________________________________________|_______________|
|                          Inferred Resources|     20,630,000|
|____________________________________________|_______________|
|Average Grade                               | 0.84ct/100m(3)|
|____________________________________________|_______________|
|Average sales value                         |    USD2,029/ct|
|____________________________________________|_______________|
|Proposed monthly throughput                 |    340,000m(3)|
|____________________________________________|_______________|
|Proposed mine life (inferred resources)     |        6 years|
|____________________________________________|_______________|
|Operating Costs                             |     ZAR45/m(3)|
|____________________________________________|_______________|
|Mining Royalties                            |         0.5-7%|
|____________________________________________|_______________|
|Capex required to bring mine into production| ZAR130,000,000|
|____________________________________________|_______________|
|Earthmoving fleet budget                    |            N/A|
|____________________________________________|_______________|
|Tax                                         |            28%|
|____________________________________________|_______________|
|IRR                                         |           123%|
|____________________________________________|_______________|
|NPV at discount values of:                  |               |
|____________________________________________|_______________|
|                                         15%|ZAR 450,436,454|
|____________________________________________|_______________|
|                                         20%|ZAR 368,824,670|
|____________________________________________|_______________|
|                                         25%|ZAR 304,043,501|
|____________________________________________|_______________|

Royalties vary according to the profitability of the mining company,
subject to a minimum rate of 0.5% and maximum rate 7.0% for diamonds.

Tirisano Preliminary Assessment

The Tirisano Project is a past producer that has been on care and
maintenance since 2008.  The 10,805.57 ha property is located some 35
km due north of the town of Ventersdorp, in the Northwest Province
approximately 150 km west of Johannesburg.  Rockwell is acquiring the
Project from Etruscan Diamonds (see news release dated March 24,
2010).  The acquisition will be completed once the mining rights have
been ceded to Rockwell.

Mining from the Tirisano project by open cast methods took place from
2002 - 2008 by the previous operator. Prospecting, geophysical surveys,
drilling comprising 2,391 boreholes, totalling 53,576 metres, and
bulk-sampling activities have been taking place since 1979.

Tirisano occurs in a karst environment where the dolomite walls of the
host-rock are vertical. The mode of gravel deposition is not typical
fluvial alluvial, but periodic subsidence has taken place during
deposition which has been ongoing since, at least, the Mesozoic period,
resulting in a build-up of a very thick gravel sequence.  The gravel
stratigraphy comprises an upper gravel horizon and a lower gravel unit
that are both economically diamondiferous, separated by a sub-economic
fine-grained pebble-clay unit.  Mineralisation is confined to the
gravel packages in-filling karst caverns etched out of the chert-rich
dolomites of the Malmani Group.  The clay-poor Lower Gravel Package and
Upper Gravel Package units are considered to be the major exploration
targets as the diamond grades encountered in these units have,
historically, supported commercial mining ventures.

A preliminary assessment, based on both indicated and inferred
resources, has been completed in support of the planned trial-mining
operation. The assessment is preliminary in nature, and includes
inferred mineralization that is considered too speculative geologically
to have the economic considerations applied to them that would enable
them to be categorized as mineral reserves, and there is no certainty
that the preliminary assessment will be realized.

The preferred method of extracting alluvial gravels at Tirisano is by
means of opencast mining. The diamondiferous deposits range from thin
tabular horizons to thick ( 60 metres) unconsolidated to semi
consolidated, gravel units infilling palaeokarst hollows and sinkholes.

Rockwell decided to re-engineer the entire concentration and recovery
process before putting the mine back into production.  Numerous
mineralogical and metallurgical studies were initiated in order to
determine the most effective methods for processing the clay-rich
gravels that can cause recovery inefficiencies. The Company is
constructing a processing facility that consists of 8 16 foot rotary
pans that includes an over designed front end to be able effectively
break down the clay inherent in the ore body. Since no diamonds have
been sold from the Tirisano mine, no current values are available and
the early 2008 value of USD606 carat has been applied for the resource
estimate.  Nevertheless, sales values of diamonds from the district are
in the USD700 per carat range, and can be expected during 2011.

At a proposed 180,000 cubic metres per month throughput, the preliminary
estimation of mine life is 11.7 years, based on indicated mineral
resources only.  An additional 7.1 years may be added if inferred
mineral resources are included, resulting in a total expected mine life
of 18.8 years. Rockwell has determined that the NPV of the Tirisano
project at a 15% discount rate is USD 32.3 million. The net present
value (NPV) at a discount rate of 20% is USD21.8 million.

The key parameters and results are tabulated below:

 ____________________________________________________________
|Key Parameters                              |Key Results    |
|____________________________________________|_______________|
|Volume of gravel                            |   Cubic Metres|
|____________________________________________|_______________|
|                         Indicated Resources|     25,279,800|
|____________________________________________|_______________|
|                          Inferred Resources|     15,334,000|
|____________________________________________|_______________|
|Average Grade                               | 2.37ct/100m(3)|
|____________________________________________|_______________|
|Average sales value                         |      USD606/ct|
|____________________________________________|_______________|
|Proposed monthly throughput                 |    180,000m(3)|
|____________________________________________|_______________|
|Proposed mine life                          |      18.8years|
|____________________________________________|_______________|
|Operating Costs                             |     ZAR49/m(3)|
|____________________________________________|_______________|
|Mining Royalties                            |         0.5-7%|
|____________________________________________|_______________|
|Capex required to bring mine into production|  ZAR73,000,000|
|____________________________________________|_______________|
|Earthmoving fleet budget                    |            N/A|
|____________________________________________|_______________|
|Tax                                         |            28%|
|____________________________________________|_______________|
|IRR                                         |            59%|
|____________________________________________|_______________|
|NPV at discount values of:                  |               |
|____________________________________________|_______________|
|                                         15%|ZAR 226,070,559|
|____________________________________________|_______________|
|                                         20%|ZAR 153,092,925|
|____________________________________________|_______________|
|                                         25%|ZAR 105,432,364|
|____________________________________________|_______________|

*Royalties vary according to the profitability of the mining company,
subject to a minimum rate of 0.5% and maximum rate 7.0% for diamonds.

During 2011, trial-mining and continued pre-feasibility studies are
planned to determine the mine-plan which will be implemented to put the
Tirisano mine back into full production.  During this time, it is
expected that the planned modifications to the plant will result in
improved grade recoveries.  Further, the sale of at least 5,000 carats
on the open market will result in a realistic, current valuation of the
diamonds.

No regulatory authority has approved or disapproved the information
contained in this news release.

Forward Looking Statements

Except for statements of historical fact, this news release contains
certain 'forward-looking information' within the meaning of applicable
securities law. Forward-looking information is frequently characterized
by words such as 'plan', 'expect', 'project', 'intend', 'believe',
'anticipate', 'estimate' and other similar words, or statements that
certain events or conditions 'may' or 'will' occur. Although the
Company believes the expectations expressed in such forward-looking
statements are based on reasonable assumptions, such statements are not
guarantees of future performance and actual results or developments may
differ materially from those in the forward-looking statements.

Factors that could cause actual results to differ materially from those
in forward-looking statements include uncertainties and costs related
to exploration and development activities, such as those related to
determining whether mineral resources exist on a property;
uncertainties related to expected production rates, timing of
production and cash and total costs of production and milling;
uncertainties related to the ability to obtain necessary licenses,
permits, electricity, surface rights and title for development
projects; operating and technical difficulties in connection with
mining development activities; uncertainties related to the accuracy of
our mineral resource estimates and our estimates of future production
and future cash and total costs of production and diminishing
quantities or grades if mineral resources; uncertainties related to
unexpected judicial or regulatory procedures or changes in, and the
effects of, the laws, regulations and government policies affecting our
mining operations; changes in general economic conditions, the
financial markets and the demand and market price for mineral
commodities such and diesel fuel, steel, concrete, electricity, and
other forms of energy, mining equipment, and fluctuations in exchange
rates, particularly with respect to the value of the US dollar,
Canadian dollar and South African Rand; changes in accounting policies
and methods that we use to report our financial condition, including
uncertainties associated with critical accounting assumptions and
estimates; environmental issues and liabilities associated with mining
and processing; geopolitical uncertainty and political and economic
instability in countries in which we operate; and labour strikes, work
stoppages, or other interruptions to, or difficulties in, the
employment of labour in markets in which we operate our mines, or
environmental hazards, industrial accidents or other events or
occurrences, including third party interference that interrupt
operation of our mines or development projects.

For further information on Rockwell, Investors should review Rockwell's
annual Form 20-F filing with the United States Securities and Exchange
Commission www.sec.com and the Company's home jurisdiction filings that are available at www.sedar.com.

Information Concerning Estimates of Indicated and Inferred Resources

This news release also uses the terms 'indicated resources' and
'inferred resources'. Rockwell Diamonds Inc advises investors that
although these terms are recognized and required by Canadian
regulations (under National Instrument 43-101 Standards of Disclosure
for Mineral Projects), the U.S. Securities and Exchange Commission does
not recognize them. Investors are cautioned not to assume that any part
or all of the mineral deposits in these categories will ever be
converted into reserves. In addition, 'inferred resources' have a great
amount of uncertainty as to their existence, and economic and legal
feasibility. It cannot be assumed that all or any part of an Inferred
Mineral Resource will ever be upgraded to a higher category. Under
Canadian rules, estimates of Inferred Mineral Resources may not form
the basis of feasibility or pre-feasibility studies, or economic
studies except for Preliminary Assessment as defined under 43-101.
Investors are cautioned not to assume that part or all of an inferred
resource exists, or is economically or legally mineable.

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For further information on Rockwell and its operations in South Africa, please contact