Antique Cut Crystal Decanter, 19th Century

The body is crafted in thick, heavy crystal, resting on a base cut with a radiating star pattern.

Condition: rated as fair; the interior shows a uniform haze due to an opaque patina caused by the natural ageing of crystal, an amorphous material. Small chips are also visible along the lower edge of the stopper.

Crystal, like glass, is an amorphous material: its atoms are not arranged in a regular network as in a mineral crystal, but in a disordered structure, comparable to a frozen liquid. This particular structure gives it transparency and brilliance, but also makes it sensitive to certain alterations over time.

Under the effect of humidity, temperature variations, or simple prolonged contact with air, the surface of crystal can undergo chemical reactions. These transformations lead to the formation of a thin altered layer, which produces a veiled or opaque appearance.

This phenomenon, sometimes referred to as the “patina of glass,” is not a manufacturing defect but a natural consequence of the ageing of an amorphous material.

It should also be noted that when a container opacified by time, whether crystal or glass, is filled with liquid – even plain, colourless water – it almost magically regains perfect transparency!