alexandrite, Brazil, gems

Gübelin reports on the newly discovered Hematita alexandrite deposit in Minas Gerais, Brazil, discovered in 1987 and notable for producing unusually fine and relatively clean material. He describes the appearance and gemological characteristics of the alexandrite, including its pronounced color change from greenish hues in daylight to reddish or purplish red under incandescent illumination. Particular attention is given to internal features useful for identifying the Brazilian material. Among the characteristic mineral inclusions subsequently identified in Hematita alexandrite are fluorite and apatite, together with mica and fluid inclusions. The discovery was significant because Hematita rapidly became an important source of fine alexandrite at a time when supplies from the traditional Russian and Sri Lankan sources were limited.