Despite their name, Herkimer Diamonds are not true diamonds, but exceptionally clear, naturally double-terminated crystals of quartz (SiO₂). They are found primarily in Herkimer County, New York, USA, where they formed approximately 500 million years ago within cavities of Cambrian-age dolostone.

Unlike most quartz crystals, which typically develop with a single terminated end, Herkimer Diamonds grew freely within open rock cavities, allowing them to form with perfectly developed crystal points at both ends. Their remarkable transparency, natural brilliance, and well-defined geometric shape have earned them the name "diamonds," although they have a hardness of 7 on the Mohs scale, compared to 10 for true diamond.

In rare instances Herkimer Diamonds can contain fascinating natural inclusions, including water, petroleum, carbon, or tiny gas bubbles, offering a rare glimpse into the geological conditions present during their formation. These inclusions make each crystal unique and are highly valued by collectors and researchers alike.

Celebrated for their exceptional clarity, natural symmetry, and geological significance, Herkimer Diamonds are among the world's most iconic quartz crystals and remain treasured specimens for both mineral collectors and jewelry designers.

Measurements: 6,5 x 7 x 5cm (excl stand)