This fantastic specimen contains beautiful red realgar crystals clinging to a pyrite matrix, collected from the Palomo Mine in Perú. Pyrite crystals can be found throughout the matrix and are easily identifiable by their golden, metallic luster.
Realgar is an arsenic sulfide mineral with the chemical formula of AsS. Realgar is known for its lustrous red hue, with the most pristine specimens being transparent with sharp crystals. The crystal structure is typically stubby and prismatic, with botryoidal and earthy clumps known to be possible formations as well.
Following prolonged/repeated periods of time under light, realgar will alter to pararealgar. If further left exposed, the pararealgar will crumble to a yellow dust. This mineral instability has especially been experienced in museums where consistent light exposure has caused specimens to crumble over time. However, periodic exposure to light shouldn't alter realgar specimens.
Realgar contains a significant amount of poisonous arsenic, making it somewhat toxic. Therefore, washing hands following handling of realgar specimens, is recommended.
The mineral pyrite or iron pyrite is commonly referred to as Fool's Gold because its metallic luster and pale brass-yellow hue give it a superficial resemblance to gold. In the old mining days, pyrite was sometimes mistaken for gold. Pyrite is the most common of the sulfide minerals with the chemical formula FeS2. Pyrite crystals occur in many shapes and habits. Smaller (druzy) crystal aggregates may give off a beautiful glistening effects, and larger crystals may be perfectly formed, including fascinating cubes, penetration twins, and other interesting crystal forms.