CRYSTALLOGRAPHY AND MINERALOGY

FROM RUPA

What is a crystal?

a solid body bounded by naturally formed plane faces

The imaginary line passing through the center of a crystal about which it can be rotated is the...

Axis of symmetry

How many crystal systems are recognized in crystallography?

Seven

Which crystal system has three axes of equal length intersecting at right angles?

Isometric (Cubic)

The property of a mineral to break along definite planes of weakness is called...

Cleavage

On Mohs scale of hardness, which mineral is assigned a value of 10?

Diamond

What is the most common mineral group in the Earth's crust?

Silicates

The color of a mineral's powder is its...

Streak

Which mineral is known as "fool's gold?

Pyrite

A mineral that can be drawn into a wire is said to be...

Ductile

What is the name of the process by which a mineral grows from a liquid or gas?

Crystallization

The external shape of a crystal is called its...

Habit

Which of these is a copper-bearing mineral?

Malachite

The property of some minerals to glow when exposed to ultraviolet light is...

Fluorescence

What is the chemical formula for Quartz?

SiO₂

Which mineral is the primary source of lead?

Galena

A mineral that breaks with a smooth, curved surface like glass has a...

Conchoidal fracture

What is the scale used to measure the relative hardness of minerals?

Mohs Scale

 Which mineral is commonly used as pencil "lead"?

Graphite

The weight of a mineral compared to the weight of an equal volume of water is its...

Specific gravity

Which crystal system has three unequal axes all at right angles?

Orthorhombic

"Iceland Spar" is a transparent variety of which mineral?

Calcite

Which mineral group is characterized by the SO₄^2- ion?

Sulfates

The way a mineral surface reflects light is its...

Luster

Which mineral is an ore of aluminum?

Bauxite

What is the hardest known natural substance?

Diamond

  A twin crystal in which the two parts are related by a 180-degree rotation is a...

Rotation twin

Which mineral is often used in the manufacture of plaster of Paris?

Gypsum

The "Tiger's Eye" gemstone is a variety of...

Quartz

Which mineral reacts with dilute hydrochloric acid to produce bubbles of CO₂?

Calcite

A mineral that can be cut into thin sheets is said to be...

Sectile

What is the most common sulfide mineral?

Pyrite

Which mineral is used as a lubricant due to its extreme softness?

Talc

The crystal system with three unequal axes, one of which is not at a right angle to the other two, is...

Monoclinic

Which mineral is the main source of mercury?

Cinnabar

"Peacock ore" is a common name for...

Bornite

Which mineral is number 1 on Mohs scale?

Talc

The property of a mineral to transmit light is...

Diaphaneity

Which mineral is a common salt used in food?

Halite

A mineral that shows different colors when viewed from different angles has...

 Pleochroism

Which crystal system has four axes?

Hexagonal

The "Ruby" and "Sapphire" are varieties of which mineral?

Corundum

Which mineral is strongly magnetic?

Magnetite

A mineral that can be hammered into thin sheets is...

Malleable

What is the basic building block of all silicate minerals?

Silicon-oxygen tetrahedron

Which mineral is a double-refracting variety of calcite?

Iceland Spar

The "Emerald" is a green variety of...

Beryl

Which mineral is commonly used in the manufacture of glass?

Quartz

A mineral that continues to glow after the light source is removed is...

Phosphorescent

Which mineral group includes the "Micas"?

Phyllosilicates

The "Amethyst" is a purple variety of...

Quartz

Which mineral is number 7 on Mohs scale?

Quartz

A crystal that lacks any symmetry is in the...

Triclinic system

Which mineral is an ore of tin?

Cassiterite

The "Cat's Eye" effect in minerals is known as...

 Chatoyancy

Which mineral is commonly used as a source of phosphorus for fertilizers?

Apatite

The "star" effect in some sapphires and rubies is...

Asterism

Which mineral is the primary source of iron?

Hematite

A mineral that can be easily carved with a knife is...

Soft

Which mineral is used in making drilling mud due to its high density?

Barite

The "Aquamarine" is a blue-green variety of...

Beryl

Which mineral is number 9 on Mohs scale?

Corundum

The symmetry of a crystal is described by its...

Point group

What is the name of the scale used to describe the tenacity or resistance of a mineral to breaking, crushing, bending, or tearing?

Tenacity