The dark red color of red beryl is attributed to {{chem2|Mn^{3+} }} ions. Red beryl rough crystals can be easily distinguished by hexagonal crystal systems. This gem has been known to be confused with
pezzottaite, a
caesium analog of beryl, that has been found in Madagascar and more recently Afghanistan; cut gems of the two varieties can be distinguished from their difference in
refractive index. Red beryl is similar to emerald and dissimilar to other beryls in that it has
inclusions like feathers and fractures. Some mineral inclusions include
quartz,
feldspar,
hematite, and bixbyite. The hexagonal channels of red beryl are primarily unoccupied and no detectable water has been found within. Red beryl gets its color from natural
chemical doping, whereby Mn3+O6 replaces AlO6 at certain positions. The deep color Mn3+O6 may be in part explained by the
Jahn-Teller effect on spin disallowed transitions. == Formation ==