This section is for those who want to go one step deeper in learning about diamonds. If you haven't read The Basics yet, we recommend you start there first.

Types of clarity inclusions

There are many clarity imperfections that can be found in diamonds. It's also pretty common for a diamond to have one or more of these, so there’s no need to immediately dismiss a diamond when you see them on a lab report. However, it’s important to keep a close look out for inclusions size and location. Not all inclusions should be evaluated equally. Inclusions on or near a diamond’s table (the flat facet on its surface) tend to be the most obvious to see.

Proceed with caution for the following:

  • Chip - a missing piece on a diamond's surface, typically caused by accidental knocks or drop

  • Laser Drill Hole - irreversible tunnels created by laser drilling often used to remove other inclusions 

  • Cavity - a deep opening in a diamond's surface, usually caused by a crystal falling out during the cutting or polishing process

  • Feather - Crack, fracture, or other break in the diamond (larger sizes are a bigger concern)

  • Crystal - a mineral trapped in the diamond (more obvious when not colorless, otherwise tend to be ok)

  • Knot - A crystal that reaches the surface of a polished diamond 

Other types of inclusions:

  • Pinpoint - tiny crystals that look like dot on a microscope

  • Needle - tiny crystals that look like rods on a microscope 

  • Cloud - areas of haziness or cloudiness

  • Twinning Wisp - small lines that are usually only seen under a microscope caused by a diamond stopping, then restarting growth

  • Bruise - a small area of impact leaving an indent

  • Indented Natural - an area of the rough diamond surface that dips below the polished diamond

  • Natural - an area of the rough diamond surfaced that was left untouched during the polishing process

  • Extra Facet - facet created intentionally to remove an inclusion

  • Graining - tiny hazy streaks on diamonds surface seen under a microscope (similar to graining on wood)

Ideal Diamond Measurements

Diamond measurements play a critical role in the beauty of a diamond. Unless you’re looking for a uniquely rare shape, try to narrow your search to the following ranges for each diamond type.

Generally speaking, you’ll also want to keep the girdle (outermost edge of a diamond) range between thin to slightly thick and culet (point at base of a diamond) range between none to small

What is the difference between Old Mine (antique) and Brilliant (Modern) cuts?

Old Mine is a style of cutting a diamond developed in the 17th century when cuts were done by hand. They were designed to sparkle under candlelight, which was the main source of light at the time. Old mine cuts have larger facets, a higher crown, and a smaller table. This allows more light through them increasing the diamond’s fire.

Brilliant is a style of cutting a diamond developed in the early 20th century, designed more for artificial light (like lightbulbs). Brilliant cuts have smaller facets, a lower crown, and a larger table. This provides the appearance of more sparkle as more light is trapped within the diamond. 

Bonus: A more recent emerging cut was developed in the 1990s to maximize a diamond's sparkle and fire by decreasing the size of facets on the bottom of the stone. This is commonly referred to as a ‘crushed ice’ cut since they give the appearance of shattered glass or ice. 

GIA lookup Tool 

When comparing diamonds, note the GIA number or ask the sales associate for it. This is a perfectly fair question to ask, and you can use this tool to look them up later!

How to know if you're getting a good price on a diamond?

For decades the diamond industry around the world has been using the Rappaport sheet to price diamonds. This is a guide published weekly and used for standardization and negotiation of diamond prices. Sadly, this sheet cannot be found online for free making it difficult for consumers to understand the market price of a diamond. However, there are some very useful tools out there like stonealgo.com that can be helpful in viewing market trends or even searching for estimated values of specific stones. 

The Diamond Manual’s recommended online jewelry stores