The by-products resource is for the Core property only, which has a lithium JORC resource of 25.1 million tonnes grading 1.09% lithium oxide.
Notably, 74% of the Core property’s resource is within 100 metres of surface and 97% is within 150 metres of surface.
Piedmont is now updating the scoping study which will include the updated by-product resources and the June 2019 lithium resource.
Piedmont’s president and CEO Keith D. Phillips said: “The historic lithium mines in the Carolina Tin-Spodumene Belt generated a material portion of their economics from the sale of by-product minerals quartz, feldspar and mica to the large, local southeastern US industrial markets.
“These markets have continued to grow, and are currently served in part by high-cost imported material.
“We expect by-products to represent a significant – and unique – opportunity for Piedmont, and I would note that in our Scoping Study dated September 12, 2018 the by-product credits effectively reduced our cash production costs of lithium hydroxide by more than US$750/t, and we expect a similar impact in our study update due next week.”
Test work from 2018 shows the minerals are marketable
Quartz, feldspar, and muscovite mica occur as essential rock-forming minerals of the Piedmont lithium pegmatites.
Likely product specifications and marketability of quartz, feldspar and mica at the Piedmont deposit are supported by the results of the 2018 bulk sampling and metallurgical test work program.
All three minerals are used in the manufacturing of glass among other things.