Igneous rocks - Rocks formed by the solidification of molten material from far below the earths surface.

Ilmenite - An ore mineral of titanium, being an iron-titanium oxide.

Induced polarization - A method of ground geophysical surveying employing an electrical current to determine indications of mineralization.

Industrial minerals - Non-metallic, non-fuel minerals used in the chemical and manufacturing

Industries. Examples are asbestos, gypsum, salt, graphite, mica, gravel, building stone and talc.

Initial public offering - The first sale of shares to the public, usually by subscription from a group of investment dealers.

Institutional investors - Pension funds and mutual funds, managing money for a large number of individual investors.

Intermediate rock - An igneous rock containing 52% to 66% quartz.

Intrusive - A body of igneous rock formed by the consolidation of magma intruded into other rocks, in contrast to lavas, which are extruded upon the surface.

Ion exchange - An exchange of ions in a crystal with irons in a solution. Used as a method for recovering valuable metals, such as uranium, from solution,

Jaw crusher - A machine in which rock is broken by the action of steel plates.

Jig - A piece of milling equipment used to concentrate ore on a screen submerged in water, either by the reciprocating motion of the screen or by the pulsation of water through it.

Kimberlite - A variety of peridotite; the most common host rock of diamonds.