Perthite was named in 1843 for a specimen from the town of Perth, which is west of Smith Falls, Ontario. The locality of the original find is believed to be Lot 3, Concession VI, North Burgess Township, Lanark County
Perthite is used to describe an intergrowth of two feldspars. An intergrowth of albite or other plagioclase and orthoclase or microcline.

Assists one in locating mis-placed items and in discovering and understanding messages from within.