This is a TOXIC mineral. Covellite (CuS) contains approximately 66% copper by weight. The following protocols are MANDATORY:
Acute Exposure Risk:
- Dermal absorption: Copper sulfide can release copper ions through skin contact, particularly in the presence of moisture (sweat). Acute copper sulfate (related compound) poisoning through dermal absorption has been documented in occupational settings, causing hemolytic anemia, methemoglobinemia, and acute kidney injury (Park et al. , 2018, https://doi. org/10.
1002/ajim. 22892). - Ingestion risk: Copper compounds are gastrointestinal irritants and, at sufficient doses, hepatotoxic. Accidental ingestion of copper sulfide dust or contaminated water can cause nausea, vomiting, abdominal pain, and liver damage. - Inhalation risk: CuS dust is a respiratory irritant. Chronic inhalation of copper-containing dusts can cause metal fume fever-like symptoms and has been associated with occupational lung disease.
Water Reactivity:
- CuS is very slightly soluble in pure water but dissolves readily in acidic conditions and can oxidize in air to release soluble copper sulfate. NEVER immerse covellite in water used for consumption.
- Covellite also reacts with hydrogen peroxide, strong acids, and oxidizing agents.
MANDATORY PROTOCOL:
1. DISPLAY ONLY. Keep in enclosed display case. 2. NO skin contact. If handled, wear gloves. Wash hands immediately and thoroughly with soap and water after any contact. 3. NO water. No gem water, no elixirs, no bath immersion, no cleaning with water that will be reused. Water contact can leach copper. 4. NO mouth contact. Keep away from children and pets. Do not place near food preparation areas.
5. NO cutting, grinding, or polishing by end users. CuS dust is toxic. Only professional lapidaries with appropriate ventilation and PPE. 6. Store away from other specimens. Covellite can tarnish and may leave copper residue on adjacent surfaces. 7. Sun safety: Covellite will tarnish and lose iridescence with prolonged light and air exposure. Store in dark, dry conditions. Museum-quality specimens are often kept in sealed containers.
Safety: Safe to own, display, and handle — wash your hands afterward. Do not make elixirs, place it in drinking water, or ingest it, and never inhale dust from raw or broken pieces.
Temperature
Natural Covellite should usually feel cooler than plastic or resin on first touch and warm more slowly in the hand.
Scratch logic
Use 1.5 on the Mohs scale as the check, not internet myths. A real specimen should behave in line with the hardness listed above.
Surface and luster
Look for a submetallic to resinous; spectacular iridescent blue-violet-purple play of colors on cleavage surfaces surface quality rather than a painted or plastic shine.
Weight and density
The listed specific gravity is 4.6-4.76 (dense due to copper content). If a specimen feels unusually light for its size, it may deserve a second look.