The Mineral in Trenggalek

What is pyrite ?
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral’s metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool’s gold due to its resemblance to gold. Pyrite is the most common of the sulfide minerals.
Pyrite is usually found associated with other sulfides or [...]

What is copper ?
Copper is a chemical element with the symbol Cu (Latin: cuprum) and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is rather soft and malleable and a freshly-exposed surface has a pinkish or peachy color. Gold, caesium and copper are the only metallic [...]