(858) 230-7042


Best selection & prices on certified loose diamonds

William & Sons Fine Jewelers carries some of the best selection of certified loose diamonds in San Diego. With our partnered suppliers we have access to over 70,000 certified loose diamonds, all at unbeatable prices. We offer some the best prices on certified loose diamonds in San Diego. What makes us unique is that we have a diamond for every budget so that way expanding your budget is not necessary to afford the precise diamond of your desire. William & Sons Fine Jewelers will save you time spent negotiating with overpriced jewelry stores. 

Instant Diamond Inventory Look-up

Why purchase certified loose diamonds?

Before purchasing a diamond, it is critical to verify that it has undergone an unbiased and professional examination through an independent and accredited certification company. This protects you from paying for overrated and falsely advertised diamond quality.

What is a Diamond Certificate?

A diamond certificate, also called diamond grading report, diamond dossier®, Diamond Full Certificate, and Hearts & Arrows Diamond Report, is a report created by a team of certified gemologists. The diamond is evaluated, measured, and scrutinized using trained eyes, a jeweler’s loupe, a microscope, and other industry tools. A completed certificate includes an analysis of the diamond’s dimensions, clarity, color, polish, symmetry, and other characteristics. Many round diamonds will also include a cut grade on the report.

What diamond shapes do you carry?

William & Sons Fine Jewelers carries all shapes and sizes of diamonds including:

Round Brilliant Cut Diamonds
Princess Cut Diamonds (often called square shaped diamonds)
Radiant Cut Diamonds (often called Rectangular Modified Brilliant or Rectangular shaped diamonds)
Emerald Cut Diamonds (often called step-cut diamonds)
Oval Cut Diamonds (often called Oval shaped diamonds)
Pear Cut Diamonds (often called Pear shaped diamonds)
Marquise Cut Diamonds (often called Marquise shaped diamonds)
Cushion Cut Diamonds (often called Cushion Modified Brilliant or Cushion Brilliant shaped diamonds)
Asscher Cut Diamonds (often called Cut-Cornered Rectangular Modified Brilliant or Asscher shaped diamonds)
Heart Cut Diamonds (often called Heart shaped diamonds)

William & Sons Fine Jewelers Diamonds Are Certified

Every certified loose diamond sold by William & Sons Fine Jewelers has been analyzed and graded by either the Gemological Institute of America (GIA) or the International Gemological Institute (IGI). These two laboratories are among the most respected laboratories in the diamond industry and are known for their consistency and unbiased diamond grading systems. Diamonds that are accompanied by these grading reports are the most highly valued in the industry. Since all diamond shapes are very different, unique characteristics determine the quality for each shape. To learn more about different diamond shapes, visit our Jewelry Education page for more information.

Ethical Sourcing | Conflict-Free Policy

Many of our loose diamonds originate in Canada, South Africa, Australia, and Brazil. William & Sons Fine Jewelers has a zero-tolerance policy towards purchasing conflict diamonds. We purchase and sell all our diamonds through suppliers who undergo extreme measures to adhere and enforce the standards established by the Kimberley Process. All loose diamonds sold at William & Sons Fine Jewelers are warranted and conflict free. The Kimberley Process is an international process aimed to track and certify diamonds. The process requires all U.S. diamond retailers to buy diamonds from manufacturers who have proper documentation warranting that the diamonds were obtained through ethical and legitimate sources.

Have additional questions?

Contact us at (858) 230-7042 to schedule an appointment, or visit our store to browse a wide selection of elegantly handcrafted engagement rings, wedding rings, and jewelry pieces. We are also here to answer your questions by email anytime at williamandsonsjewelers@gmail.com.

Make an Appointment

Schedule a visit for a more personable shopping experience.


Diamond Essentials

Learn more about the 4 C's of diamonds &
different diamond shapes available.