0.40ct I SI1 Marquise Natural Diamond

About this 0.4ct natural marquise diamond

This 0.4ct natural marquise sits in the sub-half-carat band, graded I colour (near-colourless) and SI1 clarity (slightly-included), with a very-good cut grade and certified by IGI 823660750. Listed at 9 retailers as of October 26, 2026, with a 131% spread between the cheapest and most expensive listing. That is exactly the kind of price-discovery gap Carat Hunter was built to surface. Cut grade matters more than carat or clarity for visible brilliance. If you can shift budget toward an Excellent or Ideal cut, do it before chasing higher colour or clarity.