The chemical formula of mineral Nagyagite is indicated by AuPb(Sb, Bi)Te2 – 3S6 or Gold Lead Antimony Bismuth Iron Tellurium Sulfide. This Nagyagite is actually a Sulfide mineral. Nagyagite is also considered as a very minor ore of gold. It is also most commonly used as mineral specimen at is often found exhibiting nice and interesting appearance when viewed with the aid of polarizing light microscope. Nagyagite is only one of the few minerals composed of gold. Gold does not often combine with other elements. It seems to prefer an existence as elemental native gold. In the filed of optical mineralogy, there are few gold minerals known and most of these are tellurides, including Nagyagite. Nagyagite was first described in its type of locality at Sacaramb, Transylvania, Romania. Sacaramb was formerly Nagyag, hence the name for Nagyagite. Nagyagite is sometimes referred to as foliated telluride because of its foliated crystal habits. Another name given to Nagyagite is black tellurium for its color and tellurium content.

 

Nagyagite is most commonly found in dark lead gray color to black when viewed with the aid of petrographic polarizing light microscope. When viewed in reflected light of polarized light microscope for mineralogists, Nagyagite is most commonly found showing metallic luster. The crystal habit of mineral Nagyagite commonly includes platy to tabular as well as foliated to micaceous masses. Crystals of mineral Nagyagite are usually found opaque in appearance. Nagyagite is known to crystallize in the orthorhombic system of crystal formation. . In optical mineralogy, this orthorhombic crystal system comprises crystals having three mutually perpendicular axes, of which all are of different lengths. Nagyagite crystals are most commonly found opaque in appearance. Nagyagite is most commonly found exhibiting a perfect basal cleavage found in one direction which can be found more clearly exhibited when viewed with the aid of petrographic polarizing light microscope. It is also most commonly found showing a hackly fracture when viewed with the aid of polarized microscope used in the field of optical mineralogy. The hardness measure of mineral Nagyagite when it is evaluated using the Mohs scale method is usually ranging from 1 to 1.5. Nagyagite is also most commonly found leaving a dark gray streak when rubbed on a white porcelain streak plate. The specific gravity measure of mineral Nagyagite is also most commonly found ranging from 7.4 grams per cubic centimeters to 7.5 grams per cubic centimeters, which is considered much heavier than the average for metallic minerals. Nagyagite is most commonly found associated with other interesting minerals such as quartz, hessite, krennerite, native gold, calaverite, and sylvannite. The best filed indicators of mineral Nagyagite include color, crystal habit, softness, density, associations, and crystal habit. Nagyagite notably occurs at several localities including Romania, Western Australia, and several areas in USA.