Name/Title
Quartz on HematiteEntry/Object ID
2004.1.137Description
Chemical Composition: Cu(UO2)2Si2O7 - 6H2O
Crystal System: Triclinic System
Description: Common Name: Quartz / Hematite
Group Name:
Chemistry: SiO2 / Fe2O3
Location: Jinlong Iron Mine, China
PHYSICAL CHARACTERISTICS:
Color is as variable as the spectrum, but clear quartz is by far the most common color followed by white or cloudy (milky quartz). Purple (Amethyst), pink (Rose Quartz), gray or brown to black (Smoky Quartz) are also common. Cryptocrystalline varieties can be multicolored.
Luster is glassy to vitreous as crystals, while cryptocrystalline forms are usually waxy to dull but can be vitreous.
Transparency: Crystals are transparent to translucent, cryptocrystalline forms can be translucent or opaque.
Crystal System is trigonal; 3 2.
Crystal Habits are again widely variable but the most common habit is hexagonal prisms terminated with a six sided pyramid (actually two rhombohedrons). Three of the six sides of the pyramid may dominate causing the pyramid to be or look three sided. Left and right handed crystals are possible and identifiable only if minor trigonal pyramidal faces are present. Druse forms (crystal lined rock with just the pyramids showing) are also common. Massive forms can be just about any type but common forms include botryoidal, globular, stalactitic, crusts of agate such as lining the interior of a geode and many many more.
Cleavage is very weak in three directions (rhombohedral).
Fracture is conchoidal.
Hardness is 7, less in cryptocrystalline forms.
Specific Gravity is 2.65 or less if cryptocrystalline. (average)
Streak is white.
Associated Minerals are numerous and varied but here are some of the more classic associations of quartz (although any list of associated minerals of quartz is only a partial list): amazonite a variety of microcline, tourmalines especially elbaite, wolframite, pyrite, rutile, zeolites, fluorite, calcite, gold, muscovite, topaz, beryl, hematite and spodumene.
Best Field Indicators are first the fact that it is very common (always assume transparent clear crystals may be quartz), crystal habit, hardness, striations, good conchoidal fracture and lack of good cleavage.
Common Name: Hematite
Group Name:
Chemistry: Fe2O3, Iron Oxide
PHYSICAL CHARACTERISTICS:
Color is steel or silver gray to black in some forms and red to brown in earthy forms. Sometimes tarnished with iridescent colors when in a hydrated form (called Turgite).
Luster is metallic or dull in earthy and oolitic forms.
Transparency: Crystals are opaque.
Crystal System is trigonal; bar 3 2/m
Crystal Habits include tabular crystals of varying thickness sometimes twinned, micaceous (specular), botryoidal and massive. also earthy or oolitic. Hematite Rose is a circular arrangment of bladed crystals giving the appearance of the flower of a rose.
Cleavage is absent. However, there is a parting on two planes.
Fracture is uneven.
Hardness is 5 - 6
Specific Gravity is 5.3 (slightly above average for metallic minerals)
Streak is blood red to brownish red for earthy forms.
Best Field Indicators are crystal habit, streak and hardness
Fracture: perfect
Hardness: 4 Flourite
Luster: Vitreous
Occurrence: Notable Occurrences of amethyst are Brazil, Uraguay, Mexico, Russia, Thunder Bay area of Canada, and some locallities in the USA. For Smoky Quartz; Brazil, Colorado, Scotland, Swiss Alps among many others. Rose Quartz is also wide spread but large quantities come from brazil as do the only large find of Rose Quartz prisms. Natural citrine is found with many amethyst deposits but in very rare quantities. Fine examples of Rock crystal come from Brazil (again), Arkansas, many localities in Africa, etc. Fine Agates are found in, of course, Brazil, Lake Superior region, Montana, Mexico and Germany. Especially nice specimens come from England, Mexico, Brazil, Australia and the Lake Superior region
Specific Gravity: 3.8
Streak: white
Variety: Quartz is the most common mineral on the face of the Earth. It is found in nearly every geological environment and is at least a component of almost every rock type.
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 color 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.Collection
Suomynona Mineral CollectionAcquisition
Accession
2004.1Source or Donor
Suomynona Mineral CollectionAcquisition Method
DonationDimensions
Width
4 inDepth
3-1/4 inLength
5 inDimension Notes
Dimension taken at widest pointsLocation
Location
Room
Neil JohnsonBuilding
Attic StorageCategory
PermanentMoved By
Lehman R.Date
August 28, 2009Location
Container
LeftDrawer
Front Row / 2nd ShelShelf
Right, RightWall
NorthBuilding
Founders RoomCategory
PermanentMoved By
Lehman R.Date
August 28, 2009Location
Shelf
RightCabinet
Case # 7Room
Mentzer HallBuilding
Crater Rock MuseumCategory
Permanent
