The latest articles on DEV Community by Natural Diamond (@naturaldiamond). https://dev.to/naturaldiamond https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3996727%2F002b5c58-c60e-4e19-ba62-57264e80e943.png https://dev.to/naturaldiamond en Natural Diamond Mon, 22 Jun 2026 10:33:21 +0000 https://dev.to/naturaldiamond/i-built-a-free-diamond-price-calculator-for-south-africa-and-made-it-embeddable-20mo https://dev.to/naturaldiamond/i-built-a-free-diamond-price-calculator-for-south-africa-and-made-it-embeddable-20mo <p>South Africa has a transparency problem with diamonds. Rapaport publishes a wholesale price list every Friday, but it is paywalled and trade-only, so most buyers walk into a mall jeweller with no way to tell whether the markup in front of them is 30% or 150%.</p> <p>So I built <a href="https://naturaldiamond.co.za/diamondscope/" rel="noopener noreferrer">DiamondScope</a>: a free, no-signup web tool that takes a diamond spec (shape, carat, the four Cs) and reverse-engineers the Rapaport-equivalent baseline in rand, then shows what the same stone costs manufacturer-direct vs at a boutique vs at chain retail.</p> <h2> What it does </h2> <ul> <li>Pick shape, carat, colour, clarity and cut.</li> <li>It computes a Rapaport-equivalent ZAR baseline and the three-channel price spread.</li> <li>Paste a retail quote you have been given and it tells you how far above the wholesale baseline you are being asked to pay.</li> <li>What-if cards show how each grade change moves the price.</li> </ul> <h2> How the pricing model works </h2> <p>The engine anchors on a 1ct G/SI1/GIA-Excellent round brilliant as a 1.0 baseline, then applies coefficients for carat, colour, clarity, cut and shape. Channel prices are that baseline multiplied by observed RAP-minus / RAP-plus factors per retailer tier (manufacturer-direct sits around RAP-minus 35%, chain retail well above). It is calibrated against published manufacturer-direct quotes and refreshed periodically.</p> <p>It is deliberately an indicative reference, not a contract. For a specific stone the cutter is always the source of truth.</p> <h2> The build </h2> <ul> <li>Static site on Astro, so the calculator is plain client-side JavaScript: no backend, no accounts, no tracking.</li> <li>The whole model is a set of coefficient tables, which keeps it auditable: anyone can read how a number is produced.</li> <li>It ships SoftwareApplication JSON-LD so it is machine-readable as a tool.</li> </ul> <h2> You can embed it </h2> <p>Because it is a static page, it is embeddable. There is an embed mode that strips the site chrome, plus a copy-paste snippet on the page. Try it here: <a href="https://naturaldiamond.co.za/diamondscope/" rel="noopener noreferrer">https://naturaldiamond.co.za/diamondscope/</a></p> <p>Feedback welcome, especially on the pricing model from anyone who works in the trade.</p> showdev webdev javascript astro