A model for subduction origin and distribution of fluorite deposits in the western United States
— Albert L. Lamarre

Fluorite occurs in each of the western states in deposits of varying sizes and importance. Figure 1, which is modified from Peters (1958), shows the distribution of fluorite deposits of hydrothermal origin in the western United States and Mexico. An obvious linear trend of deposits passes through western Montana, Wyoming, central Colorado, New Mexico, west Texas and eastern Mexico. A less clearly defined trend passes through eastern Idaho, western Utah, eastern Nevada, southern California and western Arizona.

 

These fluorite deposits have two common characteristics: they are middle to late Tertiary in age and are associated with alkalic igneous rocks in places where igneous rocks have been found. Specific examples of dated occurrences are given by McAnulty and others (1963), Kottlowski (1965) and Anderson (1954). Worl (1974) gives many examples of the relation-ship of fluorite to alkalic igneous rocks.