Black Elbaite from Corrego Do Urucum, Minas Gerais, Brazil

B. E. Prescott and K. Nassau
Bell Laboratories, Murray Hill, New Jersey 07974, U.S.A.

Summary: Black tourmaline from Corrego do Urucum, Brazil, is an elbaite coloured by iron and manganese with blue, green, and pink regions. Polarized spectra show the absorption bands expected in elbaite (Fe-caused blue and green, and pink, which is probably caused by Mn). The colour distribution in the transverse sections does not conform to the symmetry of tourmaline and changes along the length of the crystals. Two distinct growth stages are indicated, separated by a partial dissolution and followed by another dissolution.

Mineralogical Magazine; September 1978 v. 42; no. 323; p. 357-359; DOI: 10.1180/minmag.1978.042.323.05
© 1978, The Mineralogical Society
Mineralogical Society (www.minersoc.org)