Rockfire Resources (AIM:ROCK) said initial ore sorting trials on material from its Molaoi zinc deposit in Greece lifted the average zinc grade by 132.5% in the first sorting stage.
The AIM-listed base metal, critical mineral and precious metal explorer commissioned TOMRA Mining to test X-Ray Transmission (XRT) sensor sorting technology on 48 quarter-core samples, weighing 65kg in total, drawn from high-grade, medium-grade and waste material at Molaoi.
Molaoi is Rockfire's 100%-owned zinc-lead-silver-germanium deposit, which carries a JORC Inferred Mineral Resource of 15.0 Mt at 7.26% zinc, 1.75% lead and 39.50 g/t silver, and the company has been drilling to upgrade that resource toward Indicated status while separately progressing a maiden JORC Inferred germanium estimate.
The initial feed grade into the sorter measured 5.85% zinc.
The first sort raised that to 13.6% zinc in the high-density ore fraction, a mass pull of 34.5%.
A second sort produced a medium-density fraction averaging 11.7% zinc, a 99.5% grade uplift from the original feed, with a cumulative mass pull of 46.8%.
A third sort yielded a lower-density fraction averaging 9.9% zinc, a 69.7% uplift from the original feed, with the highest mass pull of the three stages at 57.7% and an overall combined zinc recovery of 97.7% from the initial sample.
Read more about Rockfire Resources
- 20/10/26Rockfire hits record zinc grade at Molaoi drill hole
- 29/09/26Rockfire starts maiden germanium resource estimate at Molaoi
- 14/07/26Rockfire hits more zinc at Molaoi, infills resource panel
"These initial ore sorting tests are very promising and demonstrate that the TOMRA XRT method of sorting can distinguish between ore and waste. This is an important first determination," said David Price, chief executive officer of Rockfire.
Price said the next stage will involve supplying TOMRA with a larger bulk sample for testing under commercial conditions, material he said is likely to come from the underground workings once reopened, and confirmed the processing flow sheet for the upcoming feasibility study will include the capital and operating costs of adding an ore sorting stage ahead of the ball mill.