- published: 21 Sep 2011
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Yogo sapphires are a variety of corundum found only in Yogo Gulch, located in central Montana in the Little Belt Mountains in Judith Basin County, Montana on land once inhabited by the Piegan Blackfeet people. Yogos are typically cornflower blue in color, a result of trace amounts of iron and titanium. Gemologists consider them among the finest sapphires in the world. They have high uniform clarity and maintain their brilliance under artificial light. Because Yogo sapphires occur within a vertically dipping resistive igneous dike, mining efforts have been sporadic and rarely profitable. It is estimated that at least 28,000,000 carats (5,600 kg) of Yogos are still in the ground. Jewelry containing Yogos was given to First Ladies Florence Harding and Bess Truman and many gems were sold in Europe. However, promoters' claims that Yogos are in the crown jewels of England or the engagement ring of Princess Diana are dubious. Today, a number of Yogo sapphires are part of the Smithsonian Institution's gem collection.
Sapphire (Greek: σάπφειρος; sappheiros, "blue stone") is a gemstone variety of the mineral corundum, an aluminium oxide (α-Al2O3). Trace amounts of other elements such as iron, titanium, chromium, copper or magnesium can give corundum blue, yellow, pink, purple, orange or greenish color. Chromium impurities in corundum yield a red tint, and the resultant gemstone is called a ruby.
Sapphires are commonly worn in jewelry. Sapphires can be found naturally, by searching through certain sediments (due to their resistance to being eroded compared to softer stones), or rock formations, or they can be manufactured for industrial or decorative purposes in large crystal boules. Because of the remarkable hardness of sapphires, 9 in Mohs Scale, (and of aluminum oxide in general), sapphires are used in some non-ornamental applications, including infrared optical components, such as in scientific instruments; high-durability windows (also used in scientific instruments); wristwatch crystals and movement bearings; and very thin electronic wafers, which are used as the insulating substrates of very special-purpose solid-state electronics (most of which are integrated circuits).
Approach me with hesitation
Heard about my reputation
Lord knows I've tried to change
But fear it's too much too late
There are things I could try to say
To try and sway you either way
But I just ran out of time
And the window's closed to change your mind
Can't help what I say
Can't help what I do
So much about me I wish you never knew
You got it all figured out
You keep me at arm's length
The blood's already on my hands
No changing what you think
Can't help what I say
Can't help what I do