Fine unheated Ceylon sapphires with strong laboratory reports have appreciated roughly 5 to 15 percent per year over the past decade in dealer-to-dealer trade, with larger stones and top colours at the upper end of that range.
The drivers are structural: small-scale alluvial mining produces limited quantities of eye-clean unheated crystal; treatment is ubiquitous in the broader market, so confirmed unheated stones are a shrinking subset; Asian collectors and diaspora buyers treat fine corundum as a store of value alongside gold.
Appreciation is not linear. Commercial heated blues can flatline in weak retail years while fine unheated jumps at auction. Liquidity also matters: Ceylon unheated in the one to five carat range trades more often than Kashmir or ultra-rare Burmese reds.
Buyers should not treat past performance as guarantee. Regulatory shocks, currency moves, and lab disclosure changes can pause markets. The decade trend nonetheless explains why dealers hold fine unheated Ceylon as inventory rather than flipping heated commercial goods alone.
