Rockport, Cape Ann, Essex Co., Massachusetts (TYPE LOCALITY)
Small Cabinet, 7.2 x 4.8 x 3.2 cm
Ex. Philadelphia Academy of Natural Sciences
From the TYPE LOCALITY where it was first noted in 1866 during the Civil War, this is an OUTSTANDING, aesthetic, intensely colored danalite crystal, named after the great mineralogist. The crystal is approx. 2 cm tall. Danalite turns out to be a rare member of the helvite group, seldom crystallizing and most often found as masses in rock. Here we have a superb 3-dimensional crystal perched on matrix with amazonite feldspar and cryophilite, in quartz. According to MINDAT, cryophilite has been discredited by the IMA Mica subcommittee (betcha didn't know the world had such an important body of governors...). It is now considered on odd variety of Zinnwaldite, Fe-bearing trilithionite, or Fe-bearing polylithionite (again, according to MINDAT). The danalite crystal is 3-D, attractively displayed, and overall we hav ehere both a significant and attractive display specimen of something so rare and historic that most of us will probably never see again.