Even the famous Black Prince Ruby in the British Imperial State Crown is actually a spinel , not a ruby.
His collection includes emeralds and spinels of a staggering size (some of them are nearly 300 carats).
Examples of coexisting spinels in chemical equilibrium are uncommon at Hutter.
The spinels have low Mg number in comparison with Alpine-type peridotites, suggesting hydrothermal alteration in which Cr is preferentially retained in spinel.
Dark pink and crimson-red colors are added to the display by the presence of spinels and pyropealmandine garnets.
We've put meat behind the idea that provided the theoretical basis for understanding the specific compositions of the spinels in terms of the model that they are condensates from the vapor.
Legendary for its blood-red rubies and spinels , the Mogok stone tract of northern Myanmar also produces an amazing array of other minerals.
UCLA's Kyte, who himself favored a fireball origin for the spinels , has measured the chemical composition of hundreds of spinel samples from around the world.
Rubies were found in Burma and Ceylon, topaz, beryl, garnet, amethyst and pearl in Ceylon and Southern India, and spinels and deep blue sapphires in Afghanistan and Kashmir.
At both Bald Knob and Hutter, rhodonite is absent in samples containing manganese spinels or manganese humites.