Quartz, Chalcedony and Chlorite
| ID | 666 | |
|---|---|---|
| Mineral |
Quartz
Chalcedony Chlorite |
|
| Location | Iraí - Rio Grande Do Sul - Brazil | |
| Fluorescence | LW-UV: close SW-UV: close |
|
| Mindat.org |
View Quartz information at mindat.org View Chalcedony information at mindat.org View Chlorite information at mindat.org |
|
Mindat data
| ID | 3337 |
|---|---|
| Long ID | 1:1:3337:0 |
| Formula |
SiO2
|
| IMA Status |
APPROVED GRANDFATHERED |
| Description | Quartz is one of the most common minerals found in the Earth's crust. If pure, quartz forms colourless, transparent and very hard crystals with a glass-like lustre. A significant component of many igneous, metamorphic and sedimentary rocks, this natura... |
| Other Occurrences | Most of them... |
| Industrial | Ore for silicon, glassmaking, frequency standards, optical instruments, silica source for concrete setting, filtering agents as sand, fracing sand used in oil production. A major component of sand. High purity quartz is used as an ore for creating sili |
| Diapheny | Transparent,Translucent |
| Cleavage |
The rhombohedral cleavage r |
| Tenacity | brittle |
| Colour | Colorless, purple, rose, red, black, yellow, brown, green, blue, orange, etc. |
| Hardness (min) | 7.0 |
| Hardness (max) | 7.0 |
| Luminescence | Triboluminescent |
| Lustre | Vitreous |
| About the name | Quartz has been known and appreciated since pre-historic times. The most ancient name known is recorded by Theophrastus in about 300-325 BCE, κρύσταλλος or kristallos. The varietal names, rock crystal and Bergkristall (German), preserve the ancient usage. The root words κρύοσ signifying ice-cold and στέλλειυ to contract (or solidify) suggest the ancient belief that kristallos was permanently solidified ice. The earliest printed use of "querz" was anonymously published in 1505, but attributed to a physician in Freiberg, Germany, Ulrich Rülein von Kalbe (a.k.a. Rülein von Calw, 1527). Agricola used the spelling "quarzum" (Agricola, 1530) as well as "querze", but Agricola also referred to "crystallum", "silicum", "silex", and silice". Tomkeieff (1941) suggested an etymology for quartz: "The Saxon miners called large veins - Gänge, and the small cross veins or stringers - Querklüfte. The name ore (Erz, Ertz) was applied to the metallic minerals, the gangue or to the vein material as a whole. In the Erzgebirge, silver ore is frequently found in small cross veins composed of silica. It may be that this ore was called by the Saxon miners 'Querkluftertz' or the cross-vein-ore. Such a clumsy word as 'Querkluftertz' could easily be condensed to 'Querertz' and then to 'Quertz', and eventually become 'Quarz' in German, 'quarzum' in Latin and 'quartz' in English." Tomkeieff (1941, q.v.) noted that "quarz", in its various spellings, was not used by other noted contemporary authors. "Quarz" was used in later literature referring to the Saxony mining district, but seldom elsewhere. Gradually, there were more references to quartz: E. Brown in 1685 and Johan Gottschalk Wallerius in 1747. In 1669, Nicolaus Steno (Niels Steensen) obliquely formulated the concept of the constancy of interfacial angles in the caption of an illustration of quartz crystals. He referred to them as "cristallus" and "crystallus montium". Tomkeieff (1941) also noted that Erasmus Bartholinus (1669) used the various spellings for "crystal" to signify other species than quartz and that crystal could refer to other "angulata corpora" (bodies with angles): "In any case in the second half of the XVIIIth century quartz became established as a name of a particular mineral and the name crystal became a generic term synonymous with the old term 'corpus angulatum'." |
| Streak | White |
| Crystal System | Trigonal |
| Cleavage Type | Poor/Indistinct |
| Fracture type | Conchoidal |
| Twinning | Dauphiné law. [[1]] Brazil law. Japan law. Others for beta-quartz... |
| Thermal Behaviour | Transforms to beta-quartz at 573° C and 1 bar (100 kPa) pressure. |
| shortcode_ima | Qz |
| ID | 960 |
|---|---|
| Long ID | 1:1:960:9 |
| Variety of | 3337 |
| Entry type | 2 |
| Other Occurrences | Very common. As nodules, vein fillings, crusts in volcanic rocks. As sinter-like crusts in low- to medium temperature hydrothermal veins. Main constituent in silica-rich marine sedimentary rocks. As nodular concretions and layers in limestones and marls. As a metasomatic replacement in limestones and marls ("replacement chert"). As cement in sandstones. Replacing other minerals in pseudomorphoses. As a fossilizing material (petrified wood, coral agate). |
| Diapheny | Translucent |
| Tenacity | brittle |
| Colour | colorless, white, gray, blue, any color due to embedded minerals, multicolored specimen not uncommon. |
| Hardness (min) | 6.5 |
| Hardness (max) | 7.0 |
| About the name | Mentioned by Agricola (1546) of a stone named for the town of Chalcedon, now called Kadıköy, and is a district within the city of Istanbul, Turkey. |
| Streak | White |
| Cleavage Type | None Observed |
| Fracture type | Conchoidal,Sub-Conchoidal |
| Twinning | Quartz crystallites in the chalcedony fibers are polysynthetically twinned by the Brazil law (left- and right-handed domains). |
| UV | None in a pure specimen, however, green fluorescence in short-wave UV light is very common at many localities. |
| Comment Luster | vitreous when polished, fractured surfaces have a dull or waxy luster |
| ID | 1016 |
|---|---|
| Long ID | 1:1:1016:6 |
| Entry type | 5 |
| Diapheny | Translucent,Opaque |
| Colour | Green to black |
| Hardness (min) | 2.0 |
| Hardness (max) | 3.0 |
| About the name | From the Greek chloros (χλωρός), meaning "green", in reference to its color. |
| Streak | Colorless to pale green |
| Crystal System | Monoclinic |
| Cleavage Type | Perfect |
| shortcode_ima | Chl |
Details
Price: € 220
Dimensions: None mm x None mm x None mm
Weight: Not registered
Visibile in overview:
Notes:
None
| Symbol | Element | |
|---|---|---|
| O | Oxygen | |
| Si | Silicium |