The natural sapphires selected by MAISON ROCA embody gemological excellence and jewelry craftsmanship standards. Thermal enhancement, a traditional practice recognized and fully accepted by international gemological institutions, reveals the intrinsic beauty of certain stones without ever altering their nature.
Carried out at very high temperatures. Treatment temperatures are not identical for all stones: they depend on the internal structure, inclusions, and the desired color. Each stone reacts differently and requires a customized thermal profile; this is precisely what makes heat treatment a practice mastered by experts — not a simple “pass through fire,” but a process that adjusts temperature and duration according to the specific stone to achieve the optimal effect.
Heat treatment affects the stone’s color and, at higher temperatures, certain inclusions.
This permanent, stable, and irreversible treatment is performed after the stone’s extraction. Its purpose is to refine color, improve transparency, and reduce certain natural inclusions, while respecting the mineral integrity of the sapphire. No foreign material is added: the stone remains entirely natural; only its visual expression is enhanced.
Thermal enhancement makes it possible to obtain deep and harmonious tones — intense blue, luminous yellow, or vivid pink — that meet the most demanding aesthetic standards of high jewelry.
Invisible to the naked eye, this treatment can nevertheless be identified by gemological laboratories.
Faithful to its values, MAISON ROCA selects only natural sapphires that have undergone controlled traditional heating. Any procedure that artificially alters the color or structure of the stone — beryllium diffusion, glass filling, or undeclared treatments — is strictly excluded from our selections.
Durable, stable over time, and suitable for everyday wear, MAISON ROCA sapphires offer an exceptional balance between chromatic intensity, gemological quality, and value. Each stone is chosen for its ability to transcend time, enhance a jewelry creation, and accompany a lifetime.
Céline Maillard – Gemology Department MAISON ROCA
