Lapis Lazuli

Object/Artifact

-

Crater Rock Museum

Lapis Lazuli

Lapis Lazuli

Name/Title

Lapis Lazuli

Entry/Object ID

2014.1.153

Description

Chemical Composition: SiO2 Crystal System: Monoclinic System Description: Common Name: Lapis Lazuli Chemistry: (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2. Group: Silicates, Calcite, Sulfides Location: Chile Description: This specimen is a slab of Lapis Lazuli with one polished surface. Colors are blue, white and some tan spots. Physical Description: Lapis lazuli (pron.: /'læp?s 'læzj?la?/ or /'læzj?li/ LAP-iss LAZ-zew-ly/lee,[1] Arabic: ??????? Persian: ?????? or ???????) (sometimes abbreviated to lapis) is a relatively rare semi-precious stone that has been prized since antiquity for its intense blue color. Lapis lazuli was being mined in the Badakhshan province of Afghanistan as early as the 3rd millennium BC,[2] and there are sources that are found as far east as in the region around Lake Baikal in Siberia. Trade in the stone is ancient enough for lapis jewelry to have been found at Predynastic Egyptian and ancient Sumerian sites, and as lapis beads at neolithic burials in Mehrgarh, the Caucasus, and even as far from Afghanistan as Mauritania.[3] Crystal habit Compact, massive Crystal system None, as lapis is a rock. Lazurite, the main constituent, frequently occurs as dodecahedra Fracture Uneven-Conchoidal Mohs scale hardness 5–5.5 Luster dull Streak light blue Specific gravity 2.7–2.9 Refractive index 1.5 Other characteristics The variations in composition cause a wide variation in the above values. Physical Description: Lapis lazuli is a rock, largely formed from the mineral lazurite.[4] The main component of lapis lazuli is lazurite (25% to 40%), a feldspathoid silicate mineral with the formula (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2.[5] Most lapis lazuli also contains calcite (white), sodalite (blue), and pyrite (metallic yellow). Other possible constituents: augite; diopside; enstatite; mica; hauynite; hornblende, and nosean. Some lapis lazuli contains trace amounts of the sulfur-rich löllingite variety geyerite. Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism. Fracture: Conchoidal Hardness: 7 Quartz Luster: Waxy Rock Type: Sedimentary Specific Gravity: 2.65 Streak: Light Blue Variety: Lapis lazuli is a rock, largely formed from the mineral lazurite.[4] The main component of lapis lazuli is lazurite (25% to 40%), a feldspathoid silicate mineral with the formula (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2.[5] Most lapis lazuli also contains calcite (white), sodalite (blue), and pyrite (metallic yellow). Other possible constituents: augite; diopside; enstatite; mica; hauynite; hornblende, and nosean. Some lapis lazuli contains trace amounts of the sulfur-rich löllingite variety geyerite. Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism. Lapis lazuli is a rock, largely formed from the mineral lazurite.[4] The main component of lapis lazuli is lazurite (25% to 40%), a feldspathoid silicate mineral with the formula (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2.[5] Most lapis lazuli also contains calcite (white), sodalite (blue), and pyrite (metallic yellow). Other possible constituents: augite; diopside; enstatite; mica; hauynite; hornblende, and nosean. Some lapis lazuli contains trace amounts of the sulfur-rich löllingite variety geyerite. Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism.

Collection

RAGM Mineral Collection

Acquisition

Accession

2014.1

Source or Donor

Crater Rock Museum (unknown donors)

Acquisition Method

Gift

Dimensions

Width

6-1/2 in

Depth

1 in

Length

7-3/4 in

Location

Location

Room

Delmar Smith Hall

Building

Crater Rock Museum

Date

October 18, 2021

Location

Cabinet

K-1 rear

Wall

North

Building

Storage (old gift shop upstairs)

Category

Permanent