pyrargyrite
A sulfosalt mineral, also known as dark red silver ore. Technical term used in mineralogy.
Pyrargyrite is one of the important silver ore minerals.
The Japanese name 濃紅銀鉱 is composed of 濃 (dark), 紅 (red), 銀 (silver), and 鉱 (ore), describing the mineral's appearance and composition. The reading is on'yomi.