Aragonite group

Question 1

CaCO3

Answer 1

Aragonite

Question 2

What are the three common habits of aragonite?

Answer 2

• acicular pyramidal usually in radiating groups of crystals
• tabular with prominent vertical pinacoid and prisms
• cyclic hexagonal-like twins with a basal plane

Question 3

Has a distinct pinacoidal and the prismatic is poor.

Question 4

Has a distinct pinacoidal and the prismatic is poor.

Answer 4

Aragonite

Question 5

Aragonite has a hardnes of _____

Answer 5

3.5 - 4

Question 6

It has a specific gravity of 2.94

Answer 6

Aragonite

Question 7

What are the usual color of aragonite ?

Answer 7

Colorless, white, pale yellow, and variously tinted. Luster vitreous. Transparent to translucent.

Question 8

Deposited from hot springs, and associated with gypsum. As fibrous crusts on serpentine and in amygdaloidal cavities in basalt. In metamorphic assemblages of the blueschist facies, as a result of crystallization at high pressure but relatively low temperature.

Answer 8

Aragonite

Question 9

BaCO3

Answer 9

Witherite

Question 10

Orthorhombic, with crystals always twinned on {110} forming pseudohexagonal dipyramids by the intergrowth of three individuals.

Answer 10

Witherite

Question 11

In hydrothermal veins associated with galena.

Answer 11

Witherite

Question 12

The hardness of witherite

Answer 12

3.5

Question 13

It has a specific gravity of 4.3

Answer 13

Witherite

Question 14

SrCO3

Answer 14

Strontianite

Question 15

Orthorhombic, usually in radiating clusters of acicular crystals (like type 1 of aragonite). Commonly twinned on {110} giving a pseudohexagonal appearance.

Answer 15

Strontianite

Question 16

It has a prismatic good cleavage

Answer 16

Strontianite

Question 17

Strontianite has a hardness of _______.

Answer 17

3.5 - 4

Question 18

It has a specific gravity of 3.7

Answer 18

Strontianite

Question 19

Common color of strontianite

Answer 19

White, gray, yellow, green.

Question 20

Occurs in low-temperature hydrothermal veins and deposits associated with barite, celestite, and calcite. Also present in sulfide veins, and a rare constituent of igneous rocks.

Answer 20

Strontianite

Question 21

PbCO3

Answer 21

Cerussite

Question 22

Orthorhombic crystals commonly with varied habit and many forms. Often tabular on {010}, and in reticulated groups of plates crossing each other at 60° angles.

Answer 22

Cerussite

Question 23

Has a cleavage prismatic

Answer 23

Cerussite

Question 24

Cerussite has a hardness of ______.

Answer 24

3 - 3.5

Question 25

It has a specific gravity of 6.65

Answer 25

Cerussite

Question 26

Common color of cerussite

Answer 26

Colorless, white, or gray. Luster adamantine

Question 27

An important and common supergene lead ore associated with primary minerals such as galena and sphalerite, and secondary minerals such as anglesite, smithsonite, and limonite.

Answer 27

Cerussite