From Rough to Radiance
Module 3
Selecting the Rough
Prefers flatter octahedral or macles to minimise wastage.
Planning & Marking
Master cutter maps facet junctions by eye; computer modelling is less reliable due to varied facet counts.
Shaping
The hand‑controlled bruting wheel creates an outline while maintaining thin girdle integrity.
Faceting
Facets are cut from apex downward in concentric rows; each must meet precisely at the apex to avoid a “dead” centre.
Stone must remains cool. Excess heat risks cleavage along the thin pavilion‑less body.
Stone must remains cool. Excess heat risks cleavage along the thin pavilion‑less body.
Polishing
Final gloss is achieved on a lead‑charged cast‑iron scaife using finer diamond powder.
Summary
Why it’s a specialty: A pavilionless structure leaves no margin for error; one over‑cut facet fractures the stone. Skilled labour is scarce: only ~2 % of diamond cutters globally specialise in antiques & fancy flats.