Thursday, July 29, 2010

Asscher cut diamonds

Asscher cut diamonds are square shaped. With regard to their shape, asscher cut gemstones resemble an emerald cut stone because both exhibit step cut. But, diamonds with this cut are larger than the emerald cut diamonds.

The different aspects of a diamond are arranged beautifully in asscher cut with the aim to bring out the inner beauty. Its bottom has great depth which accounts for the enormous brilliance of this type of diamond and it is characterized with ‘small table’ and ‘high crown’. One thing that you must notice while selecting your asscher cut diamond is its corners.

Monday, July 26, 2010

A Few Facts about Black Diamonds

Black diamonds are also called “carbonados,” reflecting their chemical make-up of pure black carbon. All diamonds of any color are chemically composed of carbon that through eons of time, became what we know today as diamonds. They don’t come out of the earth as white, sparkly gemstones, but must be extracted, cut and immaculately polished. Black diamonds are not truly black; they are diamonds that contain a large amount of dark inclusions that give them their dark appearance. These inclusions are actually specks of the carbon that creates all diamonds.

Black diamonds, so far, have only been mined in Brazil and Central Africa. Both countries have a well-known history of producing large, rich diamond strikes. Australia is one of the most prolific producer of diamonds and fire opals, but as yet has not hit a strike of black diamonds.

To enhance their color, black diamonds are treated with an electron beam that causes no harm to the stone. This process can be used with other colored diamonds, but is recommended only for the black diamond’s chemical carbon inclusions. The treated stone is then carefully cut into various carat weights and styles that enhance their dark color.

Monday, July 19, 2010

Diamond Cut Grades

Blue Nile Signature Ideal cut: Our most brilliant cut, representing roughly the top 1% of diamond quality based on cut. The highest grades of polish and symmetry allow it to reflect even more light than the standard ideal cut.

Ideal cut Diamonds: Represents roughly the top 3% of diamond quality based on cut. Reflects nearly all light that enters the diamond. An exquisite and rare cut.

Very good cut: Represents roughly the top 15% of diamond quality based on cut. Reflects nearly as much light as the ideal cut, but for a lower price.

Good cut: Represents roughly the top 25% of diamond quality based on cut. Reflects most light that enters. Much less expensive than a very good cut.

Fair cut: Represents roughly the top 35% of diamond quality based on cut. Still a quality diamond, but a fair cut will not be as brilliant as a good cut.

Poor cut: Diamonds that are generally so deep and narrow or shallow and wide that they lose most of the light out the sides and bottom. Blue Nile does not carry diamonds with cut grades of poor.

Wednesday, July 14, 2010

Type of Diamonds

Natural Diamonds

Natural diamonds are classified by the type and quantity of impurities found within them.

* Type Ia - This is the most common type of natural diamond, containing up to 0.3% nitrogen.
* Type Ib - Very few natural diamonds are this type (~0.1%), but nearly all synthetic industrial diamonds are. Type Ib diamonds contain up to 500 ppm nitrogen.
* Type IIa - This type is very rare in nature. Type IIa diamonds contain so little nitrogen that it isn't readily detected using infrared or ultraviolet absorption methods.
* Type IIb - This type is also very rare in nature. Type IIb diamonds contain so little nitrogen (even lower than type IIa) that the crystal is a p-type semiconductor.

Synthetic industrial diamonds

Synthetic industrial diamonds are produced the process of High Pressure High Temperature Synthesis (HPHT). In HPHT synthesis, graphite and a metallic catalyst are placed in a hydraulic press under high temperatures and pressures. Over the period of a few hours the graphite converts to diamond. The resulting diamonds are usually a few millimeters in size and too flawed for use as gemstones, but they are extremely useful as edges on cutting tools and drill-bits and for being compressed to generate very high pressures.

Thin Film Diamonds

A process called Chemical Vapor Deposition (CVD) may be used to deposit thin films of polycrystalline diamond. CVD technology makes it possible to put 'zero-wear' coatings on machine parts, use diamond coatings to draw the heat away from electronic components, fashion windows that are transparent over a broad wavelength range, and take advantage of other properties of diamonds.

Friday, July 9, 2010

Diamond Color grades

Colorless diamonds and diamonds that are yellow or yellowish brown are grouped into the categories shown below. These grades do not apply to fancy colored diamonds--they have their own color grading standards.


Nearly colorless.

Faintly tinted, usually yellow.

Lightly tinted, usually yellow. Tint can be seen with the naked eye.

Tinted, usually yellow, may progress to brownish. Tint visible to the naked eye, even when mounted.

Monday, July 5, 2010

Purple diamonds

Purple diamonds and Violet diamonds are extremely rare and often considered collector items. In nature you can find purple in lavender and orchids. It is considered precious, delicate and often associated with royalty.

Purple diamonds have the same romantic effect as pink diamonds with a touch of mystery. It is a special color which combines both red and blue – which mean it has both warmth and cool effects.

Peled Diamonds presents a wide selection of purple diamonds. You can buy the romantic fancy purple pink diamond or the mysterious and intriguing natural fancy grayish violet diamond.