Takayas Custom Jewelry Diamonds

With so many different grades and colors on the market, it can be overwhelming selecting a quality diamond. It is very important to us that you feel comfortable trusting our diamonds.

Takayas is a certified gemologist, and he personally inspects every stone that our small network of trusted gem suppliers shows us before choosing the best diamonds for our customers' budgets.

In order to maintain our high quality standards, Takayas likes to select diamonds for maximum visual brilliance that are color H or higher, Very Good to Excellent cut, and in the SI - VS clarity range unless specified otherwise. These diamonds are a great quality while still reasonably priced, and any minute imperfections are so tiny that they can only be seen under a microscope.

If you are interested in a higher grade of diamond, please let us know, and we will be happy to find one for your jewelry piece.

We want you to feel 100% comfortable working with us, and we will provide you with everything you want to know about your diamond. All of our .50 ct diamonds and up come with an official dossier or certificate from either GIA—the Gemological Institute of America or EGL—the European Gemological Laboratory—, as these are the two accepted industry-wide independent grading laboratories.

Your diamond's certificate will include a diagram of unique internal and external identifying characteristics in addition to a report detailing all of your diamond's qualities including color, clarity, weight, etc. This report will also contain a registered tracking number that has been specifically assigned to your unique stone.

Diamonds that are a .25 ct and smaller are not typically sold with a certificate, but we can provide .25 ct stones with certificates upon request.

We also work with a variety of colored diamonds. Popular diamond color options include blue, green, champagne, pink, yellow, and black.

  • Colorless
  • Pink
  • Yellow
  • Blue
  • Champagne
  • Black
Diamond Education: The 4 Cs

When it comes to selecting a diamond, the 4 Cs - cut, color, carat weight, and clarity - are the universal standard used to assess the quality of a diamond. It is useful to understand the 4 Cs so that you know what to look for in your diamond.


A diamond is cut to maximize its brilliance, and this cut is graded based on how the diamond's facets interact with light. A diamond's cut will range from Excellent to Poor based on its brightness (the amount of light it reflects internally and externally), fire (the rainbow-colored flashes of light that are reflected back when exposed to light), scintillation (the amount of sparkle), weight ratio, polish, and symmetry.



A diamond's color is graded to determine its relative absence of color- the less color, the more valuable the stone. We grade the whiteness of diamonds using a color scale which ranges from D (colorless) to Z (light yellow or brown). For higher grades of diamonds, these color distinctions are so slight that they are often invisible to the untrained eye.

Color Scale

Carat Weight

A diamond's carat weight is the standard unit of weight used to measure diamonds and other gemstones. Carat weight is measured with a highly precise electronic scale, rounded to the nearest hundredth of a carat. When choosing a diamond, it is useful to remember that a stone's carat weight is a separate measurement from its diameter. A 0.49 ct diamond may appear larger when viewed from a top-down angle in a ring's setting than a 0.50 ct diamond if it has a larger millimeter diameter across.

Carat Scale


A diamond's clarity is based on the number and size of the tiny internal imperfections (inclusions) and external imperfections (blemishes) that occur in almost all diamonds. Many of these imperfections can only be seen under a microscope, and they do not affect a diamond's beauty in any vsibly discernible way.

A diamond is assigned a clarity grade by a trained grader who will evaluate the stone under 10x magnification; this grade will range from F(flawless) to I (included).

Clarity Scale