Any of a large group of structurally similar hydrated double silicate minerals, such as hornblende, containing various combinations of sodium, calcium, magnesium, iron, and aluminum.
ETYMOLOGY:
French, from Late Latin amphibolus, ambiguous, from Greek amphibolos, doubtful, from amphiballein, to throw on either side : amphi-, amphi- + ballein, to throw; see gwel- in Appendix I.
m
f
-b
l
l
k) —ADJECTIVE
