1.66ct M SI1 Round Natural Diamond

About this 1.66ct natural round diamond

This 1.66ct natural round sits in the one-and-a-half to two carat band, graded M colour (faint-tinted) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by GIA 2547765261. Listed at 13 retailers as of November 4, 2026, with a 129% spread between the cheapest and most expensive listing. That is exactly the kind of price-discovery gap Carat Hunter was built to surface. SI-grade stones are eye-clean roughly 60 to 70% of the time at this carat range. Check the inclusion plot on the cert and ask the retailer for high-resolution video before buying.