The "hellish" origin of the famous gemstone

(NLDO) - A group of German and Australian scientists have discovered the mysterious origin of the gemstone they call "ice forged in fire".

According to Science Alert , the gemstone that scientists are trying to learn about is sapphire, which has a sparkling blue color, as cold as ice.

But authors from Heidelberg University (Germany) and Curtin University (Australia) discovered that they have extremely hot origins.

A rough sapphire gemstone excavated from the Volcanic Eifel - Photo: Sebastian Schmidt

For many years, sapphires have been found in volcanic deposits such as the Eifel Volcanic, where magma from the Earth's mantle rises into the crust over long periods of time, creating molten deposits rich in sodium and potassium.

Others are found in river beds as crystals.

But volcanoes only serve as carriers of precious stones. Exactly where they are forged remains a mystery.

In the new study, scientists considered two hypotheses: Did they form in the mantle itself, or were they smelted from other minerals as magma rose?

They collected 223 micro-sapphires from the Volcanic Eife mine and performed secondary ion mass spectrometry, which revealed the rutile and zircon impurities trapped in the sapphires as they formed, the oxygen isotope ratios in the alumina, and several other factors.

It is the things that make up a stone that tell its history.

The results showed that the place where sapphires appear must be in the Earth's deep crust instead of the mantle, which is closer to us than previously thought: just about 7 kilometers below the surface.

However, the thing that played an important role in forging it was "hell".

Some types of sapphire are created when mantle magma melts rock as it moves through, changing the composition of the Earth's crust and forging the gemstone.

Other types of sapphire form when the molten material penetrates the surrounding rock, triggering the formation of the sapphire through heat, resulting in gems with isotopic ratios more typical of mantle origin.

It is this harsh process and the mysterious color of sapphire that leads authors to call it "ice forged in fire."

The study was recently published in the scientific journal Contributions to Mineralogy and Petrology.

Source: https://nld.com.vn/bang-trong-lua-nguon-goc-dia-nguc-cua-loai-da-quy-noi-tieng-196240819105824206.htm