Danburite
Encyclopedia
Danburite is a crystalline mineral similar to topaz
.
Its chemical formula is CaB2(SiO4)2. It has a Mohs hardness of 7 to 7.5 and a specific gravity
of 3.0. The mineral has an orthorhombic crystal form. It is usually colourless, like quartz, but can be also either pale yellow, yellowish-brown, or pink. It typically occurs in contact metamorphic rock
s.
It is named for Danbury, Connecticut
, United States
where it was first discovered in 1839 by Charles Upham Shephard.
Topaz
Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al2SiO42. Topaz crystallizes in the orthorhombic system and its crystals are mostly prismatic terminated by pyramidal and other faces.-Color and varieties:...
.
Its chemical formula is CaB2(SiO4)2. It has a Mohs hardness of 7 to 7.5 and a specific gravity
Specific gravity
Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...
of 3.0. The mineral has an orthorhombic crystal form. It is usually colourless, like quartz, but can be also either pale yellow, yellowish-brown, or pink. It typically occurs in contact metamorphic rock
Metamorphic rock
Metamorphic rock is the transformation of an existing rock type, the protolith, in a process called metamorphism, which means "change in form". The protolith is subjected to heat and pressure causing profound physical and/or chemical change...
s.
It is named for Danbury, Connecticut
Danbury, Connecticut
Danbury is a city in northern Fairfield County, Connecticut, United States. It had population at the 2010 census of 80,893. Danbury is the fourth largest city in Fairfield County and is the seventh largest city in Connecticut....
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
where it was first discovered in 1839 by Charles Upham Shephard.