Chocolate mould sizes and types

Bar moulds are sold in a wide range of sizes and cavity counts, and no dimension is standardised across manufacturers. Common retail bar weights cluster loosely — small bars around 40 to 50 grams, standard bars around 80 to 100 grams — but the mould that produces them varies in depth, cavity shape and break pattern.

The practical implication is that a mould's stated capacity per cavity is the number to work from, not its outward size. Fill weight, not footprint, is what determines how many bars a batch makes.

This matters far more than the size. Polycarbonate is rigid, takes a high polish, and produces bars with gloss and sharp edges. Chocolate releases from it because properly tempered chocolate contracts as it sets and pulls away from a rigid wall.

Silicone is flexible and forgiving, and a piece can be pushed out of it even if the temper was imperfect. That flexibility is exactly why it produces a duller surface: the mould does not hold a polish and the chocolate is not released by contraction.

So the choice is a real trade-off. Polycarbonate for finish, silicone for tolerance — and if a piece will not release from polycarbonate, the answer is almost always the temper rather than the mould.

Never abrade a polycarbonate mould. The gloss on the finished chocolate is a copy of the gloss on the mould surface, and a scratch is permanent and reproduces on every bar afterwards. Wash in warm water without detergent where possible, and polish with cotton wool rather than anything textured.

Moulds should be at room temperature before filling. A cold mould sets the chocolate too fast at the surface and can produce dull patches; a warm mould delays setting and can knock the temper out.