A stone is a list of angles and indices

A faceting diagram is a recipe: for each tier, an angle on the protractor, the indices on the gear, and where to stop cutting. Get the pavilion angles wrong for the material and the light runs straight out through the back – the stone looks dark in the middle however well it is polished.

Facetmaker cuts the stone on screen exactly as the recipe says, tier by tier, so you see every facet meet before you touch the lap. It traces light through the stone as you would see it from above, shows where it leaks, and can try angles for you until it finds the ones that hold the most light.

What it does

• Eight designs to start from – round brilliant, simple round, emerald step cut, oval, cushion, princess, Asscher and trilliant.
• The material – nineteen stones from quartz to diamond with their refractive index, density and colour, and the pavilion fitted to the critical angle.
• Tiers – side, angle, start index, how many times round, mirrored or your own list of indices, and how far to cut: to the girdle, to the table or culet, to a level, to a meet point, a table width or a depth.
• Index gears – 96, 80, 72, 64 or 120, with the design converted when you change.
• Light – how much returns and how much leaks, with the head's shadow or even light, tilted or rocked, and an optimiser for the angles.
• The numbers – size, height, crown, pavilion and table proportions, the weight in carats, and what you can cut from your rough.
• The diagram – crown, pavilion and side views with the index ring, and the full table of tiers to print.
• Files – SVG of the diagram, STL of the stone in millimetres, and your cuts saved in the browser or as a file.

Beta

Facetmaker is new. Check the first meet points with a loupe as you go, as you would with any diagram.

Made for makers

Facetmaker is part of Silversalen's tools for silversmiths and hobby makers, next to Conemaker and Bezelmaker for setting the stones, Piercemaker, Filigreemaker, Kintsugimaker, Claspmaker, Linkmaker, Boxmaker, Signetmaker, Ringmaker, Chainmaker and Bench Mandrel.