Common Opal is a specific type of opal that usually exists in one color, and has no play-of-color when flashed with light. Unlike precious opal, common opal appears to be “glassy” with transparent and translucent properties. A common blue opal or fire opal gemstone will predominantly reflect one pigment of color from any viewpoint. Please refer to the photograph below for an example of a common opal stone. Updated February 23, 2021.
Geology of Northern Salt Lake City, Utah This post summarizes the basic geology of the northern region of Salt Lake City, Utah. Some geological and hydrogeological data may be incomplete or pending review. Nonetheless, students, geologists, and earth scientists are welcome to openly use, critique, and contribute information. To do so, please refer to the…
Geology of the Chinatown Area in Los Angeles, California & Hydrogeology This post summarizes the geology of the Chinatown region, of Downtown Los Angeles California. Some geological and hydrogeological data may be incomplete or pending review. Nonetheless, students, geologists, and earth scientists are welcome to openly use, critique, and contribute information. To do so, please…
What is Precious Opal? Precious opal is any type of natural opal gemstone that shows a “play of color,” such as flakes of variable colors reflecting from inside the specimen upon white light exposure. Unlike common opal, a precious stone can reflect multiple colors from a single viewpoint. For an example of an opal stone…
John Muir Biography The Father of National Parks & Geology John Muir was a Scottish-American writer, lecturer, and an early influencer for nature, geology, wildlife, and more. He’s also known as an honorary public figure for advocating the conservation of wildlife from the mid-1800s to the early 1900s. To many, he was a self-mastered glaciologist,…
Salt Lake City North, Utah 2020 USGS 7.5 Minute Topo Map To download the Salt Lake City North Quadrangle 2020 USGS 7.5 Minute Topo Map, please use the link below. PDF Download – Salt Lake City North, UT Quadrangle 2020 USGS 7.5 Minute Topo Map
San Carlos Olivine & Peridot The San Carlos Apache Reservation is one of the earth’s richest resources olivine-rich rocks. San Carlos Olivine is a name that refers to a group of closely related minerals, with very similar chemical compositions, that are found in igneous rocks in the Apache Reservation. These olivine minerals consist of silicon…
