Dripping Spring Quartzite

The Mesoproterozoic Dripping Spring Quartzite is a resistant, purple quartzite formation found in central and southeast Arizona, USA.

It is a cliff-forming purplish unit found in the lower sections of the Apache Group, units of originally sedimentary layers, but later metamorphosed.

The Apache Group is coeval with a similar aged Proterozoic sequence of eight geologic units found in the lowest geologic sequences of the Grand Canyon, the Grand Canyon Supergroup.

The Apache Group, or some underlying Vishnu Basement Rocks (Ruin Granite), are prominently found in all of the Sierra Ancha range, the range being separated by faults from its neighboring Mazatzal Mountains west, and the Salt River to the south.

The Apache Group in descending order from youngest to oldest geologic units: