Kermesite is a mineral, specifically a rare lead antimony oxide sulfide mineral. It forms as prismatic or acicular crystals, typically with a bright red to reddish-brown color. The name "kermesite" is derived from the Arabic word "qirmiz," meaning red dye. This name emphasizes the mineral's distinctive reddish color, similar to that of a dye made from dried female scale insects of the Kermes species.
Chemically, kermesite has a complex composition, primarily consisting of lead, antimony, and oxygen, with the presence of sulfur. It usually occurs in hydrothermal veins, alongside other minerals such as quartz, calcite, and various sulfides. It is often found in association with silver and sometimes as an alteration of other lead-bearing minerals.
Kermesite possesses a high luster and can exhibit a submetallic appearance. Its crystal structure is monoclinic, and it has a moderate hardness, typically falling between 2 and 3 on the Mohs scale. When observed under a microscope, kermesite crystals often display a characteristic needle-like or fibrous habit.
Although kermesite is not widely used in industrial applications, it is highly sought after by mineral collectors due to its rarity and unique coloration. Its vivid red hue, combined with its distinctive crystal form, makes it a prized specimen.
It is important to note that kermesite can contain lead, antimony, and other potentially harmful elements. Consequently, handling kermesite specimens requires precautions to avoid any health risks associated with these elements.
