American Tungsten & Antimony (ASX:AT4) said its maiden diamond drilling program at its Antimony Canyon project in Utah intersected zones of mineralization, including visible massive to disseminated stibnite, according to an Australian bourse filing on Wednesday.

The initial drilling has focused on the Emma claim, and the initial two holes intersected the target mineralised horizon, confirming the system's continuity and width.

The intensity of mineralization was higher in the second drill hole, which also intercepted a short zone containing minor arsenic sulphides, key pathfinder minerals often associated with high-grade antimony and gold systems.

The firm's shares jumped 14% in recent trading on Wednesday.