White diamonds are selected based on the high standards of international appraisal standards [4C], and we value the individuality of the diamond that does not appear in the evaluation.

Core Jewels Diamond quality 001


The international appraisal standards [4C] applied to diamonds consist of four items: weight = carat, polishing technique = cut, transparency = clarity, and color = color.

Core Jewels Diamond quality 002


Carat (ct) is a unit of measurement of diamond weight, and 1 carat = 0.2 grams.

Core Jewels Diamond quality 003


Cutting is the only manual technique used to bring out the brilliance of a diamond, and it is graded based on polishing, symmetry, and proportion, and at Core Jewels we only use high-grade diamonds that fall under [Triple Excellent], [Excellent], and [Very Good]. Doing.

Core Jewels Diamond quality 004


Clarity is the transparency of a diamond, determined by the size, location, and number of surface flaws and inclusions. At Core Jewels, we use the [IF] class, which has extremely high clarity, and the [VS2] class, which makes it difficult to detect inclusions even with the naked eye or even with 10x magnification.

Core Jewels Diamond quality 005


As a guide for diamond color, DEF = colorless and transparent, GHIJ = almost colorless, KLM = faint yellow, NR = very light yellow, and SZ = pale yellow. Core Jewels uses classes [D] to [H].


Core Jewels uses only the highest quality [EXCEPTIONAL BLACK] black diamonds that do not dye with any color.

Core Jewels Diamond quality 001


Since there are no international appraisal standards in place to evaluate the quality of black diamonds, Core Jewels has established four appraisal standards: color, cut, presence of scratches, and luster. We evaluate the grade in three stages of [BLACK] and only carefully select and use [EXCEPTIONAL BLACK], which is the highest standard.

Core Jewels Diamond quality 002


A gemstone identification book is the result of analyzing and inspecting a gemstone from a scientific approach and identifying the type of stone. At Core Jewels, we issue a gemstone identification certificate commissioned by a specialized organization and attach it to our jewelry to prove that it is a natural diamond.

*Gemstone identification documents will be issued free of charge for diamonds of 0.3 ct or more (0.2 ct for engagement rings only) and bead diamonds of 5.0 ct or more.