the ability of a material to withstand wear from its surface
hard material used in the wearing, grinding or rubbing away by friction such as
sandpaper, emery, garnet or the like.
envelope of gases surrounding the earth and held to it by friction. It has four
• troposphere – from sea level to 8-16 kilometers (5-10 mi) above
• stratosphere - up to 48 kilometers (30 miles)
• mesosphere – up to 96 kilometers (60 miles)
• thermosphere – up to 500 kilometers (300 miles) or more
One of the most abundant inorganic (nonliving) substances in nature. The white
powder or colorless crystals are the major part of sedimentary rock,
particularly in marble, limestone and chalk, as well as in animal shell and
bones. They are used in antacids, tooth powders, white paints, cement and lime
as well as other important chemical uses.
process where sediments are joined together into hard, compact rock. Common
sedimentary cements are iron, silica and lime.
limestone or soft form of calcium carbonate made of marine shells. It is white
or light colored, fine-grained, easily broken up and liquids easily go through
splitting of a rock or mineral. Splitting in one place is one way cleavage, two
places, two way cleavage and three places three way cleavage. Some rocks do not
split cleanly but break into pieces with uneven surfaces.
process of pressing sediment together because of an increase in weight from
deposits on top or by pressure from the Earth’s movements.
changing of the Earth’s crust through folding and faulting by pressure from
sediments above or by contraction (squeezing) stress.
Sedimentary rock made up of pieces of rock or minerals in sand, silt or
A metamorphic process where crystal mineral grains are made in rocks.
process where rock sediments, particles and other materials are laid down naturally
in beds, veins or deposits.
loosening and wearing away of the Earth’s surface.
igneous material that has been ejected or poured out onto the Earth’s surface.
Mixed material deposited by glacier ice and made up of clay, silt, sand, gravel
mass of land ice by the compacting (squeezing together) of snow. It flows
slowly down slope under its own weight.
size or range of sizes of grain particles or mineral grains in a sediment or
Minerals are rated 1-10 according to hardness on the Mohs’ Scale of hardness. 1
is very soft (talc) and 10 is very hard (diamond). Your fingernail is about 2.
An acid with a strong odor that is highly corrosive (wears away), toxic and
part of the Earth that is water, including liquid water, ice and water vapor on
the surface, underground or in the atmosphere.
Rocks formed when hot magma in the Earth cools rapidly and becomes a solid.
Magma forced out of the Earth’s surface makes extrusive igneous rocks (obsidian
and pumice) while magma that fills in between layers of rocks and cools slowly
is called intrusive igneous rocks (granite).
Molten, hot liquid material, forced into older rocks or between rock layers,
which hardens before it reaches Earth’s surface.
part of the Earth’s mantle 1,000 kilometers below the surface.
solid or land part of the Earth made up of the crust and upper mantle.
hot rock (molten) material made inside the Earth’s surface which make up
inside part of the Earth below the crust and above the core. It goes down to a
depth of 3480 kilometers below the surface.
bowl like vessel used to crush a substance into powder using a pestle.
Sedimentary or Igneous rocks that have been changed by heat, pressure or
Naturally occurring nonliving (inorganic) substances with a definite chemical
makeup, crystal forms, and chemical and physical properties.
A flat or
Medium to course grained intrusive igneous rock made by the hardening of magma.
quality that describes something or how something works.
works against (opposes) something like the flow of current.
different stages Earth’s materials may go through when they go from one kind of
a rock to another.
solid parts of the Earth’s crust. Most are made up of a combination of
made up of parts of older rocks, which have been broken up and carried away,
then deposited gradually, usually in layers.
of rock or mineral that are carried by wind, water or ice, which end up in
layers on the surface of the Earth.
of the powder making up rocks that we get by rubbing the rock or mineral across
a piece of unglazed tile.
a rock looks or the way a rock or mineral is made up, such as the grain size or
of several large, movable blocks of a continent or ocean crust that move as one
natural breakdown of rocks and minerals by the air and other things like wind,
rain and temperature changes.