Resists scratching better than anything else you can wear and is graded on the four Cs.
Also called: diamond accent, lab-grown diamond
Measurement
Mohs 10
The basics
What to know about diamond
Diamond is carbon crystallized into a structure so tightly bonded that nothing else in nature scratches it. That is what Mohs 10 means: it marks every other material and none marks it. Hardness is not toughness, though. Diamond has cleavage planes, directions along which the crystal splits, so a sharp knock on the thin girdle at the stone's edge can chip it.
Grading uses four measures. Cut controls how much light returns to your eye and matters most for sparkle. So a well cut smaller stone outperforms a poorly cut larger one. Color runs from D, colorless, down to Z, noticeably yellow. Clarity runs from flawless to included, and most inclusions in the SI grades are invisible without ten times magnification. Carat is weight rather than size: one carat is 0.2 grams, and a one carat round diamond measures about 6.5 millimeters across.
Price steps at round numbers, so a 0.90 carat stone costs meaningfully less than a 1.00 carat one you could not tell apart. In daily use the surprise is grease. Diamond attracts oil, and a ring looks dull within a week from hand cream and cooking. Warm water, a drop of dish soap and a soft brush over the back of the stone restores it, and prongs deserve a check once a year.
In photos
Diamond on real products
See this option on different products. Open a photo for a larger view, or select the name to read its guide.
Natural diamonds crystallized one to three billion years ago, roughly 150 kilometers below the surface, where heat and pressure forced carbon atoms into a rigid lattice. Volcanic eruptions carried them upward in a rock called kimberlite, and that is where most mining happens. Mining also works river and beach deposits where the stones washed out over time.
Rough crystals are sawn, shaped into a round outline, then faceted and polished against a wheel charged with diamond dust, since nothing else will cut them. Lab grown diamonds take weeks rather than eons. One method squeezes carbon under high pressure and high temperature to copy the geological route. The other grows crystal layer by layer from carbon rich gas in a vacuum chamber. Both produce real diamond by composition, hardness and optics, and they cost far less. Sellers are required to disclose that a stone is laboratory grown.
Best for
When it works well
Engagement rings and daily worn pieces suit diamond, because nothing else survives constant contact as well.
Heirloom intent is realistic here, since the stone outlasts several settings and can be reset.
Sparkle you never have to think about is the practical benefit, as normal wear does not dull the surface.
Small accent stones give real diamond at low cost, where a fraction of a carat adds light without a large price.
