A deep red to brownish-red variety of garnet, an iron-aluminum silicate mineral. Used in geology, mineralogy, and sometimes as a gemstone.
Almandine is a mineral in the garnet group that is particularly rich in iron.
The Japanese name 鉄礬柘榴石 is a compound of 鉄 (iron), 礬 (alum, referring to aluminum), and 柘榴石 (garnet), reflecting its composition as an iron-aluminum garnet. The reading てつばんざくろいし follows standard on'yomi for the kanji.