Sheffield Resources (ASX: SFX) has announced best-ever mineral sands grades in WA, share price up 150% since June. The company's flagship project is its world-class (both in terms of size and grade) Thunderbird mineral sands project in Western Australia, where it has today announced the highest-ever grades from the third batch (comprising 63 infill and extension drill holes) of assay results from its 2013 air-core drilling program. The outstanding results include 55.5m @ 10.0% HM from 4.5m (THAC352) (including 19.5m @ 21.0% HM from 12m) and 46m @ 12.4% HM from 30.5m (THAC404) (including 28m @ 17.9% HM from 32m). Sheffield Resources in on of our Portfolio stocks.