Catalyst Metals (ASX:CYL) said the mineral resource estimate for the Cinnamon deposit, located on the Plutonic gold belt in Western Australia, grew by 370% to 6.9 million tonnes at 2.5 grams per tonne for 541,000 ounces, according to a Monday Australian bourse filing.

This includes an open pit and underground resource of 2.9 million tonnes at 1.2 g/t for 108,000 ounces and 4 million tonnes at 3.4 g/t for 434,000 ounces, respectively. Upfront capital costs for the underground development are estimated at AU$35 million.

Its maiden underground ore reserve of 232,000 ounces at 3 g/t underpins a life of mine production target with a 7.5-year mine life, reaching steady state production of 40,000 ounces per annum to 50,000 ounces per annum. Life of mine all-in sustaining costs are estimated at AU$2,357 per ounce.

Metallurgical test work completed on Cinnamon mineralization indicates gold recoveries of 90% for the underground and 92% for the open pit.

Its shares rose 1% in recent trading on Monday.