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HEMATITE [ Oxides and Hydroxides : Hematite ]

Fe2O3, iron Oxide; Very important ore of iron, as a pigment and as mineral specimens

Hematite has several varieties, each with their own unique names.

Hematite Rose is a circular arrangment of bladed crystals giving the appearance of the flower of a rose.

Tiger iron is a sedimentary deposit of approximately 2.2 billion years old that consists of alternating layers of silver gray hematite and red jasper, chert or even tiger eye quartz.

Kidney Ore is the massive botryoidal form and gives the appearance of lumpy kidney-like masses.

Oolitic Hematite is a sedimentary formation that has a reddish brown colour and an earthy luster and is composed of small rounded grains.

Specularite is a micaceous or flaky stone that is sparkling silver gray and sometimes used as an ornamental stone.

Hematite is an important ore of iron and it’s blood red colour (in the powdered form) lends itself well in use as a pigment. Hematite gets its name from a greek word meaning blood-like because of the colour of its powder. Ancient superstition held that large deposits of hematite formed from battles that were fought and the subsequent blood that flowed into the ground. Crystals of Hematite are considered rare and are sought after by collectors as are fine Kidney Ore specimens.

Physical Characteristics

Colour : steel or silver gray to black in some forms and red to brown in earthy forms. Sometimes tarnished with irredescent colours when in a hydrated form (called Turgite)

Luster : metallic or dull in earthy and oolitic forms

Transparency : Crystals are opaque

Crystal System : trigonal; bar 3 2/m

Crystal Habits : include tabular crystals of varying thickness sometimes twinned, micaceous (specular), botryoidal and massive. also earthy or oolitic

Cleavage : absent however there is a parting on two planes

Fracture : uneven

Hardness : 5 – 6

Specific Gravity : 5.3 (slightly above average for metallic minerals)

Streak : blood red to brownish red for earthy forms

Associated Minerals : include jasper (a variety of quartz) in banded iron formations (BIF or Tiger iron), dipyramidal quartz, rutile, and pyrite among others

Major Occurrences : especially nice specimens come from England, Mexico, Brazil, Australia and the Lake Superior region

Best Indicators : crystal habit, streak and hardness

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