安裝中文字典英文字典辭典工具!
安裝中文字典英文字典辭典工具!
|
- Natural Diamonds | Diamond Stone – GIA C
Get to know all you need about diamond – the history, facts, quality factors, treatments, imitations and much more here at GIA
- Diamond History and Lore
The world’s love of diamonds had its start in India, where diamonds were gathered from the country’s rivers and streams Some historians estimate that India was trading in diamonds as early as the fourth century BC
- Diamond Description
Diamond’s characteristic chemical composition and crystal structure make it a unique member of the mineral kingdom Diamond is the only gem made of a single element: It is typically about 99 95 percent carbon The other 0 05 percent can include one or more trace elements, which are atoms that aren’t part of the diamond’s essential chemistry
- GIA Diamond Research
Natural Diamond Mining In addition to its value as a gemstone, diamond has enormous scientific value as a window into hidden processes occurring deep inside the earth Given the sheer volume of diamonds passing through its laboratories, GIA is uniquely positioned to observe and learn from diamonds in way that no other research group can Diamonds are the deepest derived material humans are
- Diamond - Gemological Institute of America
Diamond Most diamonds formed more than a billion years ago! They form about 100 miles (161 kilometers) below the earth’s surface, where the temperature and pressure are just right Diamonds are the hardest natural material on earth They stand for fearlessness and invincibility, and are a symbol of love
- Diamond Fun Facts
Diamond crystals are brought closer to the Earth’s surface through volcanic activity Diamonds can be found in shallow alluvial deposits where the crystals settle after being transported away from the kimberlite pipes by geologic activity and rivers Around 30 percent of the diamonds mined worldwide are gem-quality
- 天然钻石 | 钻石 - GIA
钻石只在地球表面之下大约 100 英里的高温和高压条件下形成。 钻石的碳原子在所有方向上的键合都基本相同。 另一种矿物 - 石墨，同样也仅包含碳，但其形成过程和晶体结构却大不相同。 石墨十分柔软，您可以用它写字，而钻石则十分坚硬，两块钻石相刻仅仅产生刮痕。 钻石描述 钻石的历史与
- Gemological Institute Of America | All About Gemstones - GIA
Established in 1931, GIA is an independent nonprofit that protects the gem and jewelry buying public through research, education and laboratory services
|
|
|