Bacon Opal: Candy Stripe Opal

Bacon opal is a hyalite opal, which is generally colorless, but the mineral impurities give it a wide range of colors. This opal is also UV reactive.

Bacon Opal is a hyalite opal. Hyalite opal is a colorless version of common opal. Hyalite form principally by alteration of volcanic rock or alteration of siliceous sinter (a type of hot spring deposit).

Bacon Opal often described as “impure” opalite (hyalite rock). They lack the famous “fire” & rainbow colors of gem-grade opal. but due to inclusions of hematite and other minerals the hyalite opal in bacon is red, yellow, white, pink and shades between those colors. 

It's unknown exactly when Bacon Opal was discovered, but the area has been inhabited by Native Americans for over 1,000 years, and more recently in the 1800's by Mormon settlers.

The Utah opalite is a sample from a paleo-hot spring deposit. This material has been nicknamed "bacon opal" or "candy opal" or "candy stripe opal". The color banding is the result of differing amounts of impurities in individual opalite layers. The Colors are due to iron, magnesium, manganese, titanium, aluminum, and antimony.

Natural Bacon Opal or Candy Stripe Opal from Thomas Range, Utah, USA Photo credit: James St. John

Bacon opal was formed during the Tertiary period sometime between 65 - 2.58 million years ago and mineralization in the mountains is very diverse. The opal is formed as a result of geothermal fluids flowing through volcanic rock layers. The area is still very geologically active, so much so there is a geothermal plant about 1 mile from the collecting site.  

The opal has several names including Lee's Opal, Bubble Opal, Banded Opal, Bacon Opal, and Wildfire Opal. The bacon appearance is a result of various iron minerals such as hematite, which give the opal layers a red color. The color bands in this material are very unique and make fun, colorful cabochons.

Bacon Opal is only found in one location in the world in western Utah, in the Thomas Mountain Range near the city of Milford in Beaver County.

Ntural Bacon Opals from Utah. Photo: James Mooney/IG

Natural Bacon Opal or Candy Stripe Opal from Thomas Range, Utah, USA Photo credit: James St. John

Natural Bacon Opal or Candy Stripe Opal from Thomas Range, Utah, USA Photo credit: James St. John

Natural Bacon Opal or Candy Stripe Opal from Thomas Range, Utah, USA Photo credit: James St. John

 

Another natural opalite is this cinnabar in opal, from the B&B mine in Nevada Photo: Helen Serras-Herman

See also:
Types of Opal With Photos
How Does Opal Get Its Color?
Chocolate Opal