Safflorite
Encyclopedia
Safflorite is a rare cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

 iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 arsenide mineral
Arsenide mineral
An arsenide mineral is a mineral that contains arsenide as its main anion. Arsenides are grouped with the sulfides in both the Dana and Strunz mineral classification systems.- Examples :* algodonite Cu6As* domeykite Cu3As* löllingite FeAs2* nickeline NiAs...

 with formula: (Co
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

,Fe
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

)As
Arsenic
Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...

2. Pure safflorite would be just CoAs2, but iron is virtually always present. Safflorite is a member of the three-way substitution series of arsenides known as the löllingite or löllingite
Lollingite
Loellingite, also spelled löllingite, is an iron arsenide mineral with formula FeAs2. It is often found associated with arsenopyrite from which it is hard to distinguish. Cobalt, nickel and sulfur substitute in the structure. The orthorhombic lollingite group includes the nickel iron arsenide...

 group. More than fifty percent iron makes the mineral loellingite whereas more than fifty percent nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

 and the mineral is rammelsbergite
Rammelsbergite
Rammelsbergite is a nickel arsenide mineral with formula NiAs2. It forms metallic silvery to tin white to reddish orthorhombic prismatic crystals, but is usually massive in form. It has a Mohs hardness of 5.5 and a specific gravity of 7.1....

. A parallel series of antimonide mineral
Antimonide mineral
An antimonide mineral is a mineral that contains antimonide for its main anion. The antimonides are structurally similar to the sulfides and are grouped with them in both the Dana and Strunz mineral classification systems.Examples include:* breithauptite...

s exist.

Safflorite along with the other minerals crystallize in the orthorhombic system forming opaque gray to white massive to radiating forms, Clinosafflorite has a monoclinic symmetry. It has a mohs hardness of 4.5 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 6.9 to 7.3. Twinning
Crystal twinning
Crystal twinning occurs when two separate crystals share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals in a variety of specific configurations. A twin boundary or composition surface separates the two crystals....

 is common and star shaped twins are frequently found.

It was first described in 1835 from the Schneeberg District, Erzgebirge, Saxony
Saxony
The Free State of Saxony is a landlocked state of Germany, contingent with Brandenburg, Saxony Anhalt, Thuringia, Bavaria, the Czech Republic and Poland. It is the tenth-largest German state in area, with of Germany's sixteen states....

, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

. Safflorite occurs with other arsenide minerals as an accessory in silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

 mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 districts. It alters to the arsenate erythrite in the secondary environment.
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