Fluorite with Quartz

Object/Artifact

-

Crater Rock Museum

Name/Title

Fluorite with Quartz

Entry/Object ID

2022.8.22

Description

About Fluorite Formula:CaF2As a Commodity:Fluorite (Fluorspar) Colour:Purple, lilac, golden-yellow, green, colourless, blue, pink, champagne, brown. Lustre:Vitreous, Dull Hardness:4 Specific Gravity:3.175 - 3.56 Crystal System:Isometric Member of:Fluorite Group Name:Named in 1797 by Carlo Antonio Galeani Napione from the Latin, fluere = "to flow" (for its use as a flux). The term fluorescence is derived from fluorite, which will often markedly exhibit this effect. The element fluorine also derives its name from fluorite, a major source of the element.Co-Type Localities:ⓘ Jáchymov, Karlovy Vary District, Karlovy Vary Region, Czech Republic ⓘ Breitenbrunn, Breitenbrunn, Erzgebirgskreis, Saxony, Germany Fluorite Group. Fluorite is found as a common gangue mineral in hydrothermal veins, especially those containing lead and zinc minerals. It is also found in some greisens, granites, pegmatites and high-temperature veins, and as a component of some marbles and other metamorphic rocks. About Quartz Formula:SiO2 Colour:Colorless, purple, rose, red, black, yellow, brown, green, blue, orange, etc. Lustre:Vitreous Hardness:7 Specific Gravity:2.65 - 2.66 Crystal System:Trigonal 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 bergcrystal, 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'."

Collection

John Morrow Collection

Location

Location

Display Case

DS-8

Room

Delmar Smith Hall

Building

Crater Rock Museum

Date

December 27, 2023