Inclusion

Every diamond grew with baggage. Inclusions are the internal marks left behind: mineral crystals trapped inside, feathers (fractures), clouds (clusters of pinpoints), needles (thin rods), pinpoints (tiny dots), and twinning wisps (flat, irregular planes from crystal growth stress). GIA grades clarity from Flawless (FL) down to Included (I3). FL and IF show nothing under 10x magnification. VVS1 and VVS2 hide inclusions so well that most dealers need a loupe and good lighting to find them. VS1 and VS2 inclusions are minor under magnification. SI1 and SI2 inclusions are easier to spot at 10x. I1, I2, and I3 inclusions can affect transparency and durability. Eye-clean means you cannot see inclusions without magnification at normal viewing distance, roughly 6-12 inches. For round brilliants under 1.50ct, SI1 and above is usually eye-clean. Some SI2 stones pass the eye-clean test if inclusions sit under prongs or along the girdle. I've had clients reject a VS2 because the plot diagram looked scary, then buy an SI1 that looked cleaner face-up. The plot is a map, not the whole story. Price jumps between clarity grades are steep. Moving from IF to VS2 on a 1.00ct G can save $2,000-$4,000 with no visible difference on the finger. VS2 to SI1 is where I steer most value-focused buyers. You get eye-clean appearance at a discount that funds better cut or size. Plotting diagrams on GIA certs show inclusion location and type. A feather near the girdle matters more than a pinpoint deep in the pavilion. Location affects both visibility and chip risk during setting.