Gold & Diamond Buyers of San Diego in Chula Vista's Third Avenue Village has operated from 255 Third Avenue since 2012, specializing in gold, silver, diamond, coin, and luxury-watch transactions. The firm's coin and bullion division handles graded NGC/PCGS-certified rarities alongside American Eagle and Buffalo bullion products, a category shared with corridor dealer Axiom Coin Exchange. Every item is tested in front of the seller using Thermo Scientific Niton XRF analyzers and acid-assay kits, with weight confirmed on certified scales inspected by San Diego County Weights & Measures. Offers are benchmarked to live KITCO spot prices for gold, silver, platinum, and palladium, and the shop issues itemized purchase receipts documenting alloy content, gram weight, and per-ounce calculation — documentation that Third Avenue accounting practices such as CHULA VISTA CPA reference when preparing Schedule D capital-gains filings. The operation holds BBB accreditation with an A rating and is incorporated in California as Knight Jewelry & Coin Inc. Highest-value transactions involve GIA-certified diamonds above two carats and Rolex Submariner, Daytona, and GMT-Master II references authenticated through serial-number verification and movement inspection.