### stone | igneous rock:

Andesite
* are dark gray to black
  - most abundant in subduction-related arc volcanoes
* is an igneous rock
* occur as extensive lava flows always associated with continental masses.
* range from white to black, but most are dark gray or greenish gray.
* typically occur as extensive lava flows associated with compression plate margins.

Batholith
* are igneous intrusions formed beneath the earth's surface
  - rocks
  - the largest of all igneous intrusions
* is an igneous rock
* make up the core of mountains.

### stone | igneous rock:

Pegmatite
* Some pegmatites contain tourmaline, garnet, or beryl as accessory minerals.
* are extremely coarse-grained felsic rocks.
* are igneous intrusive rocks containing extremely coarse-grained crystals
  - most famous for their large, high quality mineral specimens
* can be from a few inches to hundreds of feet thick.
* continue to be the largest source of tantalum.
* is also the source for many gem-quality precious and semiprecious stones
* very coarse-grained igneous rock made up mostly of feldspar and quartz.

Peridotite
* are a. ultramafic rocks b. rich in olivine c
  - igneous rocks
  - rich in the mineral olivine
* consists in part of the minerals olivine and pyroxene
  - primarily of olivine
* contain the same chemical makeup as the molten magma in the Earth's mantle.
* starts out as a sub-crustal, upper mantle rock.

### stone | igneous rock | peridotite:

Kimberlite
* Most kimberlites occur as multiple intrusive events.
* are everywhere
  - famous for containing diamonds
  - peridotites

Pluton
* are mappable plutonic rock bodies and are often given names
  - masses of solidified magma that are exposed after erosion removes the overlying rocks
* can include dikes and xenoliths.

Plutonic rock
* are formed when magma cools and solidifies underground
  - igneous rocks formed at great depth
  - rocks that solidified from molten rock beneath the surface of the Earth
* cools slowly deep within the earth so the crystals are larger.

Rhyolite
* are high and silica and therefore very viscous, in contrast to low viscosity basalts
* melt at lower temperatures and are lighter in weight and color than basalts.
* predominate among rock types in the Yellowstone Plateau, but basalts also occur.
* represents change, variety and progress.
* varies in texture from very fine grained and almost cherty, to more coarse and granular.

### stone | igneous rock:

Volcanic rock
* Most volcanic rocks are lavas or ashes, and obsidian is comparatively rare.
* are extrusive igneous rocks
  - visible everywhere
* can be gray, or red, or black.
* come in many colors.
* contains some radioactive minerals in tiny amounts.
* cover most of the planetary surface.
* form from Lavas which erupt at the surface and cool rapidly.
* heat underground water to boiling.
  - exported for use in making cement
* is the most common type of rock found on Earth's surface
  - principal material
  - very light
* originate in several ways.

### stone | igneous rock | volcanic rock:

Agglomerate
* have always an inhomogenous abrasion and are actually unfit for a strained area.
* volcanic rock

### stone | igneous rock | volcanic rock | tuff:

Basaltic tuff
* are black , dark green or red in colour.
+ Tuff, Basaltic tuffs: Igneous rocks
  * Basaltic tuffs are occur widely.
  * Basaltic tuffs are black, dark green or red in colour. They vary greatly in coarseness. Often submarine, they may contain shale, sandstone, grit and other sedimentary material, and are occasionally fossiliferous. Recent basaltic tuffs are found in Iceland, the Faroe Islands, Jan Mayen, Sicily, Sandwich Islands, Samoa, etc.

Welded tuff
* are products of explosive volcanism
  - so dense that they are often mistaken for lava flows
* pyroclastic flow of lava which was hot enough to weld together.
+ Tuff, Welded tuff: Igneous rocks