Stornoway Diamond Corporation (TSX-SWY) is pleased to announce the May 5, 2010 SEDAR filing of a National Instrument ("NI") 43-101 technical report for the recently Updated Preliminary Assessment at the Renard Diamond Project in North Central Québec. The Renard Diamond Project, which includes the Renard kimberlite pipes and the Lynx-Hibou system of kimberlite dykes, is a 50:50 joint venture with SOQUEM INC. ("SOQUEM").

Highlights of the NI 43-101 technical report (previously reported by Stornoway on March 22, 2010) include:

• On a pre-tax basis, Net Present Value and Internal Rate of Return are C$885 million (at an 8% discount rate) and 24.8% respectively using a September 2009 diamond valuation of US$117/carat and a US dollar exchange rate of C$1.11.
• Base case estimates of after-tax Net Present Value and Internal Rate of Return at C$538 million and 20.5% respectively.
• A conceptual mine life of 25 years based on a production rate of 1.8 million tonnes per year and a total diamond production of 30 million carats.
• Pre-production capital cost of C$450 million, including contingencies, which increases to a total capital cost of C$511 million after sustaining capital and closure cost.
• Average life of mine operating cost of C$39.45/tonne in a conceptual mine plan utilizing both open pit and underground mining.

The preliminary assessment is based on Indicated Mineral Resources and Inferred Mineral Resources, and is preliminary in nature. Inferred Mineral Resources are considered too geologically speculative to have mining and economic considerations applied to them that would enable them to be categorized as Mineral Reserves. Mineral resources that are not mineral reserves do not have demonstrated economic viability. There is no certainty that the Preliminary Assessment will be realized.

Qualified Persons for the NI 43-101 Report

The authors of the NI 43-101 technical report are Mr. Normand Lecuyer (ing.) and Dr. William E. Roscoe (P.Eng.) of Scott Wilson Roscoe Postle Associates Inc., Mr. David Farrow (P.Geo.) of Golder Associates Ltd., Ms. Alexandra Kozak (P.Eng.) of AMEC Americas Ltd. and Mr. Marc L'Ecuyer (ing.) of Stantec Experts-conseils ltée. David Farrow is the independent Qualified Person responsible for the preparation of the mineral resource estimate for the Renard Diamond Project.

Stornoway Diamond Corporation

Stornoway Diamond Corporation is one of Canada's leading diamond exploration and development companies, involved in the discovery of over 200 kimberlites in seven Canadian diamond districts. The Company benefits from a diversified diamond property portfolio, a strong financial platform and management and technical teams with experience in each segment of the diamond "pipeline" from exploration to marketing.

SOQUEM INC.

SOQUEM is a wholly-owned subsidiary of Société générale de financement du Québec ("SGF"). SGF is the Québec government's main industrial and financial development corporation. Its mission is to undertake economic development projects in the industrial sector in cooperation with partners and in compliance with the economic development policies of the Government of Québec.

On behalf of the Board
STORNOWAY DIAMOND CORPORATION
/s/ "Matt Manson"
Matt Manson
President and Chief Executive Officer

For more information, please contact Matt Manson (President and CEO) at 416-304-1026
or Nick Thomas (Manager Investor Relations) at 604-983-7754, toll free at 1-877-331-2232
Pour plus d' information, veuillez contacter M. Ghislain Poirier (Vice-président Affaires Publiques) au 418-780-3938 ou gpoirier@stornowaydiamonds.com
**  Website: www.stornowaydiamonds.com  Email: info@stornowaydiamonds.com **

This document contains "forward-looking information" within the meaning of Canadian securities legislation and "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995. This information and these statements, referred to herein as "forward-looking statements" are made as of the date of this document and the Company does not intend, and does not assume any obligation, to update these forward-looking statements, except as required by law.

Forward-looking statements relate to future events or future performance and reflect current expectations or beliefs regarding future events and include, but are not limited to, statements with respect to: (i) the amount of mineral resources and potential mineral deposits; (ii) the amount of future production over any period; (iii) net present value and internal rates of return of the proposed mining operation; (iv) capital costs, including plant costs, and operating costs; (v) diamond values and increases in diamond values; (vi) strip ratios, rates of extraction of kimberlite and mining rates; (vii) expected time frames for repayment of borrowed funds; (viii) anticipated dilution of mineralized material; (x) anticipated breakage in processing; (x) mine expansion potential; (xi) exploration potential at the Project; (xii) road construction and operation costs; and (xiii) expected time frames for completion of permitting and regulatory approvals, proceeding to a Feasibility Study and making a production decision. Any statements that express or involve discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions or future events or performance (often, but not always, using words or phrases such as "expects", "anticipates", "plans", "projects", "estimates", "assumes", "intends", "strategy", "goals", "objectives" or variations thereof or stating that certain actions, events or results "may", "could", "would", "might" or "will" be taken, occur or be achieved, or the negative of any of these terms and similar expressions) are not statements of historical fact and may be forward-looking statements

All forward-looking statements are based on Stornoway's or its consultants' current beliefs as well as various assumptions made by and information currently available to them. Many of these assumptions are set forth in the news release and include: (i) the presence of and continuity of diamonds in its host rocks at the Project at modeled grades; (ii) the capacities of various machinery and equipment; (iii) the availability of personnel, machinery and equipment at estimated prices; (iv) exchange rates; (v) diamond values and diamond price escalation factors; (vi) discount rates; (vii) tax rates and royalty rates applicable to the proposed mining operation; (viii) financing structure and costs; (ix) diamond recovery and breakage, (x) reasonable contingency requirements; (xi) anticipated financial performance, (xii) receipt of regulatory approvals on acceptable terms within commonly experienced time frames; (xiii) the settlement of an Impact and Benefits Agreement on acceptable terms within a reasonable time frame. Although management considers these assumptions to be reasonable based on information currently available to it, they may prove to be incorrect. Many forward-looking statements are made assuming the correctness of other forward looking statements, such as statements of net present value and internal rate of return, which are based on most of the other forward-looking statements and assumptions herein. The cost information is also prepared using current values, but the time for incurring the costs will be in the future and it is assumed costs will remain stable over the relevant period.

By their very nature, forward-looking statements involve inherent risks and uncertainties, both general and specific, and risks exist that estimates, forecasts, projections and other forward-looking statements will not be achieved or that assumptions do not reflect future experience. We caution readers not to place undue reliance on these forward-looking statements as a number of important factors could cause the actual outcomes to differ materially from the beliefs, plans, objectives, expectations, anticipations, estimates assumptions and intentions expressed in such forward-looking statements. These risk factors may be generally stated as the risk that the assumptions and estimates expressed above do not occur, including the assumption in many forward-looking statements that other forward-looking statements will be correct, but specifically include, without limitation, risks relating to variations in the grade, kimberlite lithologies and country rock content within the material identified as mineral resources from that predicted, variations in rates of recovery and breakage; the greater uncertainty of potential mineral deposits, developments in world diamond markets, slower increases in diamond valuations than assumed, risks relating to fluctuations in the Canadian dollar and other currencies relative to the US dollar, increases in the costs of proposed capital and operating expenditures, increases in financing costs or adverse changes to the terms of available financing, if any, tax rates or royalties being greater than assumed, results of exploration in areas of potential expansion of resources, changes in development or mining plans due to changes in other factors or exploration results of Stornoway or its joint venture partners, changes in project parameters as plans continue to be refined, risks relating to receipt of regulatory approvals or settlement of an Impact and Benefits Agreement, the effects of competition in the markets in which Stornoway operates, operational and infrastructure risks and the additional risks described in Stornoway's most recently filed Annual Information Form, annual and interim MD&As, and Stornoway's anticipation of and success in managing the foregoing risks. Stornoway cautions that the foregoing list of factors that may affect future results is not exhaustive. When relying on our forward-looking statements to make decisions with respect to Stornoway, investors and others should carefully consider the foregoing factors and other uncertainties and potential events. Stornoway does not undertake to update any forward-looking statement, whether written or oral, that may be made from time to time by Stornoway or on our behalf, except as required by law.