Spain Girl Fashion Ruby Diamond Engagement Ring 173

Spain Girl Fashion Ruby Diamond Engagement Ring.   

By Farzana Aamir

s.

Rubies have a hardness of 9.0 on the Mohs scale of mineral hardness. Among the natural gems only moissanite and diamond are harder, with diamond having a Mohs hardness of 10.0 and moissonite falling somewhere in between corundum (ruby) and diamond in hardness

South Sudan Girl Fashion Ruby Diamond Engagement Ring 172

 South Sudan Girl Fashion Ruby Diamond Engagement Ring.   

By Farzana Aamir

Ruby is α-alumina (the most stable form of Al2O3) in which a small fraction of the aluminium3+ ions are replaced by chromium3+ ions. Each Cr3+ is surrounded octahedrally by six O2− ions.

South African Girl Fashion Ruby Diamond Engagement Ring 171

South African Girl Fashion Ruby Diamond Engagement Ring.   

By Farzana Aamir

 This crystallographic arrangement strongly affects each Cr3+, resulting in light absorption in the yellow-green region of the spectrum and thus in the red color of the gem. When yellow-green light is absorbed by Cr3+, it is re-emitted as red luminescence

Somalian Girl Fashion Ruby Diamond Engagement Ring 170

 Somalian Girl Fashion Ruby Diamond Engagement Ring.   

By Farzana Aamir.

A DIAMOND IS FOREVER. SINCE WHEN?

This red emission adds to the red color perceived by the subtraction of green and violet light from white light, and adds luster to the gem's appearance. When the optical arrangement is such that the emission is stimulated by 694-nanometer photons reflecting back and forth between two mirrors, the emission grows strongly in intensity. This effect was used by 

Solomon Islands Girl Fashion Ruby Diamond Engagement Ring 169

Solomon Islands Girl Fashion Ruby Diamond Engagement Ring.  

By Farzana Aamir

Slovenian Girl Fashion Ruby Diamond Engagement Ring 168

Slovenian Girl Fashion Ruby Diamond Engagement Ring.  

By Farzana Aamir 

 In the 1870s, though, miners began discovering huge veins of diamonds in South Africa, and ice started flooding onto world markets. Diamonds had quickly gone from 

 being a scarce gem to a pretty common commodity, which was bad news for everyone in the diamond business who wanted to fetch high prices for their wares. These mine owners realized they would have to be clever if they wanted to keep getting top dollar for an increasingly common gem.

Slovakian Girl Fashion Ruby Diamond Engagement Ring 167

Slovakian Girl Fashion Ruby Diamond Engagement Ring.

 By Farzana Aamir 

While engagement rings have been around for centuries, diamonds are a fairly late addition to the party. For many years, there simply weren’t all that many diamonds on the world market, so diamond engagement rings were pretty rare. The rock Archduke Maximilian of Austria gave to Mary of Burgundy in 1477 was an early exception.

Despite that high-profile ring, things stayed pretty quiet on the diamond front through the late 19th century.