Infill drilling at South Ayawilca intersected several zones of high-grade zinc (silver-lead) mineralisation associated with gently dipping sulphide-rich mantos hosted by limestones, with highlights 25.9m grading 10% zinc and 15 grams per tonne of silver including 13.7m grading 15.9% zinc and 26g/t silver.

A step-out hole, 75m west of the existing inferred resource intersected several high-grade but narrow zinc-silver-lead veins with highlights including 0.9m grading 13.7% zinc, 0.6% lead and 133g/t silver.

Tinka said hole A20-170 intersected a better than expected zone of high-grade zinc mineralisation at South Ayawilca.

"This hole hit high-grade silver-zinc-lead mineralisation as well as massive pyrrhotite at shallower than usual depths, suggesting that replacement of limestone by sulphides is much thicker in this area than previously recognised," said Tinka president and CEO Dr Graham Carman.

Tinka has completed about 2,500m in seven drill holes of the current programme, which is expected to extend into early 2021.

Shares in Tinka Resources are trading at C20c, valuing the company at $68 million.