Diamond type
Diamond type is a method of scientifically classifying diamonds by the level and type of their chemical impurities. Diamonds are separated into four types: Type Ia, Type Ib, Type IIa, and Type IIb. The impurities measured are at the atomic level within the crystal lattice of carbon atoms and so, unlike inclusions, require an infrared spectrometer to detect.
Engagement ring
In the United States, where engagement rings are worn by women, diamonds have been widely featured in engagement rings since the middle of the 20th century. Solitaire rings have one diamond. The most common setting for engagement rings is the solitaire prong setting, which was popularized by Tiffany & Co. in 1886 and its six-claw prong setting design sold under the "Tiffany setting" trademark. The modern favorite cut for an engagement ring is the brilliant cut, which provides the maximum amount of sparkle to the gemstone. The traditional engagement rings may have different prong settings and bands. Another major category is engagement rings with side stones. Rings with a larger diamond set in the middle and smaller diamonds on the side fit under this category. Three-stone diamond engagement rings, sometimes called "trinity rings" or "trilogy rings", are rings with three matching diamonds set horizontally in a row with the bigger stone placed in the center. The three diamonds on the ring are typically said to represent the couple's past, present, and future, but other people give religious significance to the arrangement.