You know that the 4Cs are cut, color, clarity and carat weight, right? “So?” you might be asking…well, a gem client of mine related a story to me that I hope you find interesting.
Faceted Gemstone
She was at a holiday dinner the other night and a gentleman came up and asked her the carat weight of her amethyst. She told the person and then she asked why he asked the question. He said he was trying to picture how large a 7 carat diamond would be because he had been reading about a 7 carat engagement ring that cost one million dollars. She explained to him that her 18 carat amethyst was not a good gage of how big a 7 carat diamond would be.
“What?” you might be asking yourself. A carat is the same no matter what gemstone, right? Well, it is true that a carat is a standard weight. A carat is equal to 0.2 grams; 5 carats equal 1 gram and 141.7 carats equal an ounce.
Colored Gemstones and Diamonds
The issue when comparing the size of a colored gemstone and a diamond of the same carat weight is a matter of density, also known as specific gravity. Not all gemstones have the same specific gravity. Specific gravity is the number of times heavier a gemstone of any volume is than an equal volume of water, i.e., specific gravity is the ratio of the density of the gemstone to the density of water. For example, ruby / sapphire is heavier than a diamond therefore a 1 carat diamond is larger than a 1 carat sapphire / ruby. An amethyst is lighter than a diamond so a 1 carat diamond would be smaller than a 1 carat amethyst. Amethyst has a specific gravity of 2.65, diamond 3.51 and ruby / sapphire 3.96 – 4.05.
In math terms density is the mass per unit volume of gem. Its unit is gram/cm3. Confused? Most gemstone books have charts that will give you the specific gravity of any gemstone so you don’t have to guess.
Rare and Semi Precious Gemstones
AfricaGems.com carries many colored beautiful natural gemstones of many sizes and diamonds too. Check them out by clicking here.
Faceted Gemstone
She was at a holiday dinner the other night and a gentleman came up and asked her the carat weight of her amethyst. She told the person and then she asked why he asked the question. He said he was trying to picture how large a 7 carat diamond would be because he had been reading about a 7 carat engagement ring that cost one million dollars. She explained to him that her 18 carat amethyst was not a good gage of how big a 7 carat diamond would be.“What?” you might be asking yourself. A carat is the same no matter what gemstone, right? Well, it is true that a carat is a standard weight. A carat is equal to 0.2 grams; 5 carats equal 1 gram and 141.7 carats equal an ounce.
Colored Gemstones and Diamonds
The issue when comparing the size of a colored gemstone and a diamond of the same carat weight is a matter of density, also known as specific gravity. Not all gemstones have the same specific gravity. Specific gravity is the number of times heavier a gemstone of any volume is than an equal volume of water, i.e., specific gravity is the ratio of the density of the gemstone to the density of water. For example, ruby / sapphire is heavier than a diamond therefore a 1 carat diamond is larger than a 1 carat sapphire / ruby. An amethyst is lighter than a diamond so a 1 carat diamond would be smaller than a 1 carat amethyst. Amethyst has a specific gravity of 2.65, diamond 3.51 and ruby / sapphire 3.96 – 4.05. In math terms density is the mass per unit volume of gem. Its unit is gram/cm3. Confused? Most gemstone books have charts that will give you the specific gravity of any gemstone so you don’t have to guess. Rare and Semi Precious Gemstones
AfricaGems.com carries many colored beautiful natural gemstones of many sizes and diamonds too. Check them out by clicking here.
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