In the 1900s, miners found beautiful dark blue beryl crystals in the Maxixe mine in the Paiuhy region of Minas Gerais state, Brazil. Because its dark blue color wasn’t typical of beryl, Maxixe beryl created quite a stir when it appeared in the trade in 1973. Unfortunately, the beautiful colors faded rapidly when they were exposed to light or heat.
Because of the gem’s tendency to fade, its popularity declined almost as quickly as it rose.
Natural radiation creates a defect, or color center, in the atomic structure of the gem, causing its blue color. Dark blue Maxixe beryl fades at an unpredictable rate, but further irradiation can sometimes restore the blue color. Unfortunately, it fades just as rapidly if it’s exposed to sunlight or heat again.
Treaters sometimes irradiate aquamarine to produce a dark blue that resembles Maxixe beryl. The treated material’s color also fades when exposed to sunlight or heat, so like true Maxixe beryl, it’s not suitable for jewelry use.