Erebaur, precious stones in eight languages
A free encyclopedia of precious stones, a service that finds stones for clients, and a site that had to be accurate, sourced and readable from English to Arabic, on a phone as on a large screen.
The project
Erebaur has two sides. One is a free encyclopedia of precious stones: 22 chapters and 182 entries, from how deposits form to treatments, laboratories and auctions. The other is a sourcing service: Erebaur finds a stone in any producing country, has it tested by an independent laboratory and hands it over with a sourcing dossier.
The encyclopedia brings the readers; the service lives on their trust. So the substance had to hold up: every claim sourced, every figure checkable, and the same care in all eight languages. Erebaur was founded by Maxime Perriard, who runs Hallebardier.
The challenges
Four constraints, set from the start.
English, French, Spanish, Hindi, Thai, Chinese, Russian and Arabic. Arabic reads right to left, so the whole layout had to turn around, menus, tables and figures included, without a separate version.
Precious stones are full of figures copied from site to site without checking. Every claim had to point to an institutional source: laboratories, scientific journals, auction houses, regulators.
Hardness, refractive index, auction records, deposits: a table of numbers does not read on a phone. It needed figures, legible at 320 pixels wide.
Full-text search, a map of the mines, advertising that pays for the encyclopedia: all of it without slowing the pages down or opening a security hole.
Three pages of the site
Screenshots of the live site, 7 October 2026.
What was built
Static pages, built with Astro and served by Cloudflare.
Every page exists in all eight languages, at the same address under the language prefix, and Google knows which one to show to whom.
Scales, maps, timelines, matrices: 30 components draw the figures in code. They stay sharp at any size and are translated with the text.
687 citations from 235 domains, none from Wikipedia. The figures on Erebaur’s About page are recounted every time the site is built.
The properties of each stone and what the encyclopedia says about it, linked to the chapter and to the service. Plus an index of 60 stones, an atlas of the mines and an A to Z glossary.
Every chapter is checked against a schema: a badly filled figure or a chapter without its sources stops the build.
Only the scripts the site expects can run, each recognised by its fingerprint. Pages are tested at 13 widths, from 320 to 2560 pixels, in all eight languages.
The result
Measured on the live site on 7 October 2026 with Lighthouse, the testing tool from Google, and counted in the sitemap.
Performance of the home page, on a computer.
SEO and accessibility on the four pages tested on a computer, one of them in Arabic.
pages online, 65 in each of the eight languages.
citations from Wikipedia, out of 687.
The quote is free.
The rest fits in a thirty-minute call: your business, your competitors, and what a website can change. Or by phone, on +41 26 420 00 86.