Tertiary Minerals unearths higher grade copper in early drilling at Mushima North Proactive uses images sourced from ShutterstockTertiary Minerals PLC (AIM:TYM, OTC:TTIRF, FRA:TMU) told investors that early drilling results indicate that the higher-grade copper zone at its Mushima North project in Zambia continues across the northern section of Target A1. Preliminary pXRF analysis returned 45 metres at 0.41% copper and 0.28% zinc from 12 metres, including 6 metres grading 1.01% copper. Further intersections included 55 metres at 0.32% copper and 0.29% zinc, and 73 metres at 0.29% copper and 0.38% zinc. The first 12 holes also produced indicative silver readings of up to 214 grams per tonne. Tertiary cautioned that the silver readings are semi-quantitative, while all reported intersections are downhole widths with true widths currently unknown.