Sunstone Metals (ASX:STM) said the mineral resource estimate for the Bramaderos gold-copper project in Ecuador grew by 900,000 ounces of gold-equivalent, with the higher-confidence indicated category growing 200% to 600,000 ounces, according to a Monday Australian bourse filing.

The mineral resource came in at 220 million tonnes at 0.5 grams per tonne grade of gold equivalent, containing 0.33 g/t grade of gold, 0.10% grade of copper, and 1.2 g/t grade of silver for 3.6 million ounces of gold equivalent at a cut-off grade of 0.3 g/t of gold equivalent.

The resource is based on 59 drill holes for a total of 29,006 meters of drilling, and 5,385 linear meters of trenching and channelling from 32 trenches and channels.

It plans to conduct a scoping study on the project.