Guyana Goldfields Reports Robust Projected Economics from Preliminary Assessment for the Aurora Gold Project

TORONTO - Guyana Goldfields Inc. (TSX: GUY) (”Guyana” or the “Company”) is pleased to announce the on-schedule completion of a positive NI43-101 compliant Preliminary Assessment (”PA”) for the Aurora Gold Project by AMEC of Oakville, Ontario. An interim summary called “Summary of PA Key Findings” is posted on the Company’s website at www.guygold.com. The final PA NI43-101 Technical Report will be submitted within the required 45-day period and made available on Sedar and the Company website.

The PA is the first phase of a two-phase Definitive Feasibility Study. Phase 2 will take place from August 2009 to March 2010 and conclude with the submission of the Definitive Feasibility Study.

Highlights - The proposed mine plan calls for the production of more than 4 million ounces of gold - Guyana’s project economics at today’s gold price of US$ 950 per oz show a pre-tax IRR of 27%, NPV of US$ 678 million at a discount rate of 7% per year, and a payback of 3.9 years with a pre-tax cash flow of US$ 1.64 billion (AMEC’s base case results are shown below under the heading “Economics”). - An engineering solution which addresses potential flooding has been designed and consists of an embankment along the river Key Findings of the PA Geology & Resource Estimate - A resource estimate was completed using revised cut-off grades in both the open pit and the underground mine, 0.85 grams per tonne (g/T) and 2.0 g/T respectively; the indicated resource is 24.1 million tonnes at 4.1 g/T for 3.2 million ounces and the inferred resource is 12.9 million tonnes at 3.3 g/T for 1.4 million ounces Mining - The proposed design is based on a combination of surface and underground mining; the mine would start as an open pit and the conceptual design of a single pit is progressing; underground mining would follow with access through both ramps and a main shaft; preferred mining methods have been selected - The open pit tonnage in the proposed mine plan is 17.9 million tonnes at an average grade of 2.8 g/T, while the underground tonnage is 18.1 million tonnes at an average grade of 4.5 g/T Processing - The mineralized material is mainly non-refractory sulphides (hard rock) with a small portion of oxides (saprolite) near surface calling for conventional gold milling with recoveries above 95% - A process flow which incorporates a Semi-Autogenous Grinding (SAG) and ball mill combination as well as gravity and Carbon In Pulp (CIP) circuits has been designed and key equipment has been identified - Average throughput (for the first 9 years) - 8,000 tonnes per day - Total gold produced - 4.0 million ounces - Average annual gold production - 250,000 ounces (based on 16 full years of production) Water Management - River embankment - the design and engineering of an embankment (river dyke) is well advanced; this dyke is designed to protect a small area of the northern portion of the site from potential flooding during exceptional events - Surface water - an extensive surface water management system, including drainage, ponds and diversion ditches, is being designed and engineered to manage and control surface water in a tropical environment Logistics & Infrastructure - On-site infrastructure - conceptual design is advanced; this includes a main gate, new airstrip, roads and accommodations Schedule - Development & Construction - 2 years (2010-2012) - First year of open pit production - 2012 - Open pit life - 9 years (2012-2020) - First year of underground production - 2015 - Underground life - 14 years (2015-2028) - Total mine life - 17 years (2012-2028) - 16 full years of production Economics - Capital expenditures - Pre-production development (surface & open pit) - US$ 262M - Surface equipment - US$ 21M - Underground development - US$ 147M - U/G equipment - US$ 10M - Sustaining (includes closure) - US$ 80M - Operating Cash Costs of US$ 364 per oz - AMEC’s base case project economics, at a gold price of US$ 750 per oz, show a pre-tax IRR of 16.3%, NPV of US$ 236 million at a discount rate of 8% per year, and a payback of 6.0 years with a pre-tax undiscounted cash flow of US$ 878 million Guyana is also providing the following update: Off-site Infrastructure - Port and Road - design includes a small port facility and an access road extension; wharf and pier design as well as a secured lay-down area for the port is complete; options on the 40-km extension of the existing road are under study - Hydropower dam - site topographical survey is in progress Environmental & Social Impact Assessment (”ESIA”) and Permitting - Studies related to the ESIA are largely complete - Permitting process is proceeding well; a Preliminary Environmental Impact Assessment was submitted to the Guyanese Environmental Protection Agency in June 2009 Guyana’s internal financial model, based on the PA, establishes the following economics (all in US$): ————————————————————————- Gold Price NPV (at) 7% Cash Flow IRR Payback (years) ————————————————————————- $ 800 $ 383M $ 1,069M 19% 5.3 ————————————————————————- $ 1,000 $ 777M $ 1,832M 30% 3.6 ————————————————————————- $ 1,200 $ 1,171M $ 2,595M 39% 2.8 ————————————————————————-

Claude F. Lemasson, the President and Chief Operating Officer (COO) of Guyana, states “The on-schedule completion of this major milestone with a positive PA further demonstrates the robustness of the Aurora Gold Project. It confirms the high-grade nature of the open pit and a gold production target above 4 million ounces in a mining-friendly jurisdiction. In addition, there is significant potential in increasing the resource base over the near term. This sets a clear and solid framework around the highly profitable world-class gold mine that we plan on building at Aurora.”

The critical advancement of the Aurora project during this pre-development phase will continue with extensive drilling in the next 7 months, completion of the ESIA in Q4 2009, completion of the Hydropower Feasibility Study in Q1 2010, the issue of the Permit to build and operate the mine, as well as the completion of the Definitive Feasibility Study by AMEC in Q1 2010.

The Aurora Gold Project, located in north central Guyana in South America, is a multi-million ounce gold discovery being advanced through key studies leading to the start of construction in 2010.

AMEC employees Richard Kilpatrick P.Geo (Geology), Jeff Smith P.Geo. (Resources), Benny Zhang P.Eng. (Mining), Lionel Magumbe P.Eng (Process), and Xiaogang Hu P.Eng. (Geotechnical and Water Management) are the AMEC “Qualified Persons” for the Purposes of National Instrument 43-101, Standards of Disclosure for Mineral Projects of the Canadian Securities Administrators, executing the PA NI43-101 Technical Report and confirm that they have reviewed the information contained within this release.

Mineral resources that are not mineral reserves do not have demonstrated economic viability (NI43-101/3.4(e)). The preliminary assessment 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 (NI43-101/2.3(3bi)).

AMEC is an international project management and services company with Canadian operational headquarters in Oakville, Ontario. AMEC’s Mining & Metals unit provides a full range of services to the mining industry, including strategic planning and market assessments, resource and reserve estimation and auditing, mine planning and design, feasibility studies, process development, environmental services, simulations, geotechnical, engineering design, procurement, project and construction management, plant start-up and commissioning, operator training and mine support services.

Claude F. Lemasson, P.Eng., MBA, President & Chief Operating Officer of Guyana Goldfields Inc., is a professional engineer with 20 years of experience in mining construction and operations. Prior to joining Guyana, he was Goldcorp’s General Manager of Projects for Canada and U.S. and the Mine General Manager of the Red Lake mine from 2000 to 2006. He is also a graduate of the prestigious Kellogg-Schulich Executive MBA program, where he gained international perspectives on global strategic management and decision-making.

About Guyana Goldfields Inc.

Guyana Goldfields Inc. is a Canadian based mineral exploration company primarily focused on the exploration and development of gold deposits in Guyana, South America where the Company has operated since 1996. The Company is currently undertaking technical studies to advance and develop the Aurora Project in Guyana. As at the date hereof, the Company has approximately $26 million in cash and short-term bank guaranteed investment certificates and no debt.

For further information: Mr. Claude F. Lemasson, President & COO or Ms. Jacqueline Wagenaar, Director of Investor Relations, Guyana Goldfields Inc., Suite 1205-141 Adelaide Street West, Toronto, Ontario, Canada M5H 3L5, Tel: +1-416-628-5936, Fax: +1-416-628-5935, info@guygold.com, www.guygold.com/

Source: Guyana Goldfields Inc.

For further information: Mr. Claude F. Lemasson, President & COO or Ms. Jacqueline Wagenaar, Director of Investor Relations, Guyana Goldfields Inc., Suite 1205-141 Adelaide Street West, Toronto, Ontario, Canada M5H 3L5, Tel: +1-416-628-5936, Fax: +1-416-628-5935, info at guygold.com