Mexican Coconut

Object/Artifact

-

Crater Rock Museum

Name/Title

Mexican Coconut

Entry/Object ID

2013.1.15

Description

Chemical Composition: SiO2 Crystal System: Monoclinic System Description: Common Name:Quartz Chemistry: SiO2 Group: Silicates Location: Chihuahua, Mexico Description: This is a coconut geode with a double cavity. (Rare) Physical Description: Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz, several of which are semi-precious gemstones. Especially in Europe and the Middle East, varieties of quartz have been since antiquity the most commonly used minerals in the making of jewelry and hardstone carvings Fracture: Conchoidal Hardness: 7 Quartz Luster: Waxy Rock Type: Sedimentary Specific Gravity: 2.65 Streak: White Variety: Pure quartz, traditionally called rock crystal (sometimes called clear quartz), is colorless and transparent (clear) or translucent, and has often been used for hardstone carvings, such as the Lothair Crystal. Common colored varieties include citrine, rose quartz, amethyst, smoky quartz, milky quartz, and others. Quartz goes by an array of different names. The most important distinction between types of quartz is that of macrocrystalline (individual crystals visible to the unaided eye) and the microcrystalline or cryptocrystalline varieties (aggregates of crystals visible only under high magnification). The cryptocrystalline varieties are either translucent or mostly opaque, while the transparent varieties tend to be macrocrystalline. Chalcedony is a cryptocrystalline form of silica consisting of fine intergrowths of both quartz, and its monoclinic polymorph moganite.[8] Other opaque gemstone varieties of quartz, or mixed rocks including quartz, often including contrasting bands or patterns of color, are agate, sard, onyx, carnelian, heliotrope, and jasper. Pure quartz, traditionally called rock crystal (sometimes called clear quartz), is colorless and transparent (clear) or translucent, and has often been used for hardstone carvings, such as the Lothair Crystal. Common colored varieties include citrine, rose quartz, amethyst, smoky quartz, milky quartz, and others. Quartz goes by an array of different names. The most important distinction between types of quartz is that of macrocrystalline (individual crystals visible to the unaided eye) and the microcrystalline or cryptocrystalline varieties (aggregates of crystals visible only under high magnification). The cryptocrystalline varieties are either translucent or mostly opaque, while the transparent varieties tend to be macrocrystalline. Chalcedony is a cryptocrystalline form of silica consisting of fine intergrowths of both quartz, and its monoclinic polymorph moganite.[8] Other opaque gemstone varieties of quartz, or mixed rocks including quartz, often including contrasting bands or patterns of color, are agate, sard, onyx, carnelian, heliotrope, and jasper.

Collection

RAGM Mineral Collection

Acquisition

Accession

2013.1

Source or Donor

Crater Rock Museum (Misc. donors)

Acquisition Method

Gift

Dimensions

Depth

2-1/2 in

Diameter

5 in

Location

Location

Drawer

Top Shelf

Shelf

Right, Right

Wall

East

Building

Freida Smith Hall

Category

Permanent

Date

April 11, 2013

Location

Drawer

Bottom Shelf

Shelf

Right

Cabinet

Case# 36

Wall

East

Building

Freida Smith Hall

Category

Permanent