Naturally Occurring Metallic Bismuth
Native Bismuth
Synthetic Bismuth
Crystals Showing Hopper Growth - This and the following picture are of crystals
grown in a bismuth smelter. They tarnished to produced the iridescence on
the surface. This single crystal nicely displays hopper growth. Note
also the color of the metal (slightly tarnished) near the base of the crystal.
This is the view of another Bismuth crystal perpendicular to one of the hopper
faces. In this view the edge of the crystal is closest to your eye.
Each parallel face is like a step deeper towards the center of the crystal.
It is similar to an aerial view of a football stadium with the rows of seats
getting lower and closer to the the playing field.
A group of hopper
crystals.
CHEMISTRY - Bi
CRYSTALLOGRAPHY - Hexagonal
CRYSTAL GROWTH AND HABITS - Bismuth often forms crystals in parallel groups or as hoppers. It can also be reticulated, arborescent or granular.
COLOR AND OPTICAL PROPERTIES - Silver white with a slightly golden hue. It tarnishes to produce an iridescence. Opaque
HARDNESS - 2 - 2.5
SPECIFIC GRAVITY - 9.7 - 9.8
LUSTER - Metallic
STREAK - Silver white
BREAKABILITY - Perfect cleavage along {0001} (easy to produce).
OCCURRENCE - Native Bismuth is a rare mineral that occurs in hydrothermal deposits associated with cobalt, nickel, silver and tin. It is also found in pegmatites and in topaz bearing tin and tungsten veins.
ASSOCIATED MINERALS - Chalcopyrite, Arsenopyrite, Pyrrhotite, Pyrite, Cobaltite, Nickeline.
MINERAL NAME - From the German wismuth, meaning white mass.