Native arsenic is known as a rather rare mineral. 'The native arsenic under study, appearing in compact massive form, was found in the carbonate veinlets within tungsten-bearing quartz veins. The chemical composition obtained from electron microprobe analysis is 99.26% As, 0.02%S, 0.01%Fe, 0. 01%Ni, 0.07%Ag, 0.03%Sb, 0.03%Al, 0.04%Cd, totalling 99.45%· That the native arsenic is liable to oxidize is shown by the fact that the tin-white colour of a fresh fracture with metallic luster may gradually change to dark-grey when exposed in air.SEM observation shows the native arsenic appear in the form of tabular crystals. The reflectivities (λ, R) are, 470nm, 50.4; 480nm, 48.2;546nm, 47.8; 654 nm, 45.7，VHN20g=132. 5kg/mm2. The strongest lines in X-ray analysis are; 2.772 (10)，3.531(7)，2.053 (5) 1.881(4)，1.556(4).