Mainstream Minerals to Earn a 100% Interest in a Lithium / Rare Earth Project 10/7/2009 2:21 PM - NW (via Thenewswire.ca) Mainstream Minerals Corporation (TSX-V: MJO) (the "Company") announces that it has entered into a Property Option Agreement with Mr. Perry English, on behalf of Rubicon Minerals Corporation (the "Optionor"), for an option to acquire a 100% interest in a lithium / rare earth property located near Raleigh Lake in Raleigh Township in the Kenora Mining Division, Ontario. Raleigh Lake's lithium bearing pegmatites have been known in the area since the 1960's. Provincial government mapping in the 1990's identified a 'Pegmatite Field' trending through the area. A detailed surface exploration program was also completed in 2000 and consisted of linecutting, lithogeochemical bedrock sampling and pegmatite evaluation. The Lithogeochemical survey consisting of hundreds of bedrock samples identified several extensive north-south bedrock trends interpreted to reflect large buried or unexposed pegmatite bodies. One trend is comprised of multiple anomalies over a broad area, and extends for 1.8 kilometres in length and 500 metres in width. This lithogeochemical survey was very successful in delineating bedrock anomalies over most parts of the grid for all three elements Li (Lithium), Rb (Rubidium), and Cs (Cesium). Of importance is the Johnson Pegmatite which has a strong anomaly. It is so far exposed for almost 100 metres with an 8 metre width at surface. This dyke is enriched in Lithium, Cesium, Niobium, Tantalum and very high Rubidium values. Channel sample results included highs of: 9.0 metres grading 0.557% Li (Lithium), 981.0 g/t Rb (Rubidium), 83.0 g/t Cs (Cesium), 95.0 g/t Nb (Niobium) and 125.0 g/t Ta (Tantalum). 3.0 metres grading 5,340.0 g/t Rb (Rubidium), 239.0 g/t Cs (Cesium) and 99.0 g/t Nb (Niobium) and 62.00 g/t Ta (Tantalum). Historic data taken was from the Ontario Government geological files. Under the terms of the Option Agreement, Mainstream Minerals can earn a 100% interest by completing payments to the Optionor as follows: On signing of the Agreement $8,000.00 1st Anniversary of the Agreement $12,000.00 2nd Anniversary of the Agreement $16,000.00 3rd Anniversary of the Agreement $25,000.00 4th and final Anniversary of the Agreement $35,000.00 In addition to the cash payment schedule, Mainstream Minerals shall issue to the Optionor, shares in the Company as follows: On signing of the Agreement 50,000 Common Shares 1st Anniversary of the Agreement 50,000 Common Shares 2nd Anniversary of the Agreement 50,000 Common Shares The Optionor will retain a 1.5 % Net Smelter Return (the "NSR") interest in the Property Rare Earths Demand for rare metals and rare earth elements is soaring because of consumer demand for more fuel-efficient cars, alternative energy technologies such as fuel cells, the nuclear power industry for both practical and experimental utilization, rechargeable batteries, lasers, hydrogen storage, superalloys as used in the aerospace industry, televisions, computer screens, cell phones, permanent magnets as used in electric-hybrid vehicles and in the conductor industry for many of the new "Green" technologies, etc. Currently, 97% of the world supply of the Rare Earth Materials (REM) comes from China. China recently announced a major reduction in the exports of REMs coming out of their mines. This decision will considerably reduce the supply for buyers outside of China while world demand is in full growth. For example Rubidium and Cesium, which are not actively traded, have both recently sold for as much as $100.00 US per gram. Mainstream Minerals is planning an exploration program which will consist of compilation of all previous data, stripping of the Johnson Pegmatite, a detailed mapping program of abundant lithium / rare earths bearing pegmatite outcrops located on the Raleigh Lake property and a tightly spaced detailed magnetometer program to better define the known geological structures. About Mainstream Minerals Mainstream Minerals Corporation is a mineral exploration and development company focused on precious metal / rare earths mining properties with economic potential, with the aim of bringing such properties to commercial production. The Bobjo Mine project is located in the prolific Red Lake Gold Camp in Ontario. MJO Shares Outstanding: 26,676,087 ON BEHALF OF THE BOARD Signed "Michael Romanik" Michael Romanik, President & CEO (204) 222-0137 info@mainstreamminerals.com www.mainstreamminerals.com This news release includes certain forward-looking statements concerning