(au. ag)2te4 is known as sylvanite. does anyone know its real name?

The real name of is Silver gold telluride or sylvanite.

Explanation:

This mineral was first found in Transylvanian Romania and hence it was named as Sylvanite. It contains an element called Tellurium. Molecular weight is 429.89gm. The color of sylvanite is mostly grey, white, pale yellow and silver white.

Its Hardness ranges from 1.5 - 2 and it is Opaque in Transparency.  In prismatic, bladed, and columnar precious stones. Likewise grainy, monstrous, encrusting, in veins, and in dendritic arrangements.