0.51ct J SI1 Marquise Natural Diamond

About this 0.51ct natural marquise diamond

This 0.51ct natural marquise sits in the half to three-quarter carat band, graded J colour (near-colourless) and SI1 clarity (slightly-included), with a standard cut grade stated by the retailer rather than the lab and certified by GIA 5556453982. Listed at 5 retailers as of October 30, 2026, with prices from $452 to $601, a $149 spread on the same certified stone. Blue Nile lists it at $601. 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.