Reference
Crystal Care Guide
Water safety, sunlight sensitivity, fragility, and handling notes for every stone in our encyclopedia. Based on mineral science, not guesswork.
Never Put in Water
Keep Out of Sunlight
Toxic - Handle With Care
Contain lead, arsenic, antimony, or mercury. Wash hands after handling. Never use for gem elixirs.
Why Some Crystals Can't Get Wet
Water damage in minerals happens through three mechanisms. Dissolution - some minerals (selenite, halite) are water-soluble and literally dissolve. Chemical reaction - iron-bearing minerals like pyrite react with water to form acids that damage the specimen. Absorption - porous minerals (turquoise, opal) absorb water, which can change color, weaken structure, or carry contaminants into the stone.
Sunlight fading occurs when UV photons destabilize the color centers in certain minerals. The same iron impurities that create amethyst's purple, when hit by UV light, gradually lose their radiation-induced color configuration. This process is irreversible. There are two exceptions to that pattern: tenebrescent minerals (hackmanite, tugtupite) change color in light and reverse in the dark, which is not damage, and water-bearing gems (opal, pearl, amber) are harmed by the heat and dehydration of direct sun rather than the light itself.
Sun labels here are verify-or-omit: a stone is only flagged when its light sensitivity is documented in the mineralogical literature. "No Known Sun Risk" means exactly that, no documented sensitivity, not a blanket guarantee.
Complete Care Reference
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains arsenic. Display only. Wash hands after handling. Beautiful but toxic.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Organic gem. Avoid chemicals, perfumes, heat. Clean with damp cloth.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Prolonged sunlight exposure fades purple color. Display away from windows.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Traditionally 'treated matrix' using a century-old sugar-sulfuric acid process (fully disclosed, GIA-accepted). Treated pieces are stable once processed. Untreated crystal opal needs standard opal care (hydration-sensitive). Brief rinse only. Avoid heat.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains lead. Wash hands after handling. Very soft and fragile. Display only.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Perfect basal cleavage. Very fragile. Handle with extreme care.
Clean with dry or slightly damp cloth. Store away from harder minerals.
TOXIC: Contains arsenic. Produces garlic odor when struck. Wash hands after handling. Display only. Never heat or grind.
Clean with dry or slightly damp cloth. Store away from harder minerals.
EXTREMELY fragile. Delicate crystal tufts crush on contact. Display only. Store in padded display case.
Slowly converts to malachite naturally. Avoid water, heat, and acids.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Dense and durable. Safe for water. Used in hot stone massage due to excellent heat retention. Handle carefully when heated.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Durable (Mohs 7.5) but color-zone boundaries can be stress points. Avoid thermal shock - rapid temperature changes can cause internal fracture along zone interfaces. Safe for mild soap and water. Avoid ultrasonic cleaning for stones with visible inclusions.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Lab-grown rainbow surface may tarnish over time. Avoid water.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Organic fossilized resin, soft (Mohs 2.5). Avoid alcohol, perfume, solvents, and acetone - they can cloud or damage the surface. Avoid heat and sunlight (can crack). Clean with soft damp cloth only. The blue fluorescence is preserved by keeping the surface undamaged.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
DISSOLVES IN WATER. Store in completely dry environment with desiccant packets. Even humidity can damage. Display in enclosed case.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Very durable (Mohs 8). Safe for jewelry and cleaning. Has basal cleavage so avoid sharp impacts along that plane.
Ironstone backing provides stability but opal layer is still sensitive to heat and dehydration. Avoid ultrasonic cleaners.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains arsenic minerals. Never use for gem elixirs. Wash hands after handling.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Dissolves in water. Very soft. Clean with dry cloth only. Store carefully.
Durable. Safe for cleaning with mild soap and water.
Feldspar cleavage + delicate chatoyant inclusions. Avoid impacts that could damage the cabochon dome or disrupt internal fiber alignment. Brief rinse only. Store separately in soft pouch.
Stacked parallel terminations are more fragile than simple quartz points - the smaller secondary tips can chip with impact. Safe for water and mild soap. Store standing upright and padded to protect the termination structure.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Fragile, fades in light, and softens in water. Ideal display conditions only.
Sulfide mineral that oxidizes when wet. Acid-treated 'peacock' surfaces may dull over time. Keep dry.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Porous and soft. Brief rinse acceptable but don't soak.
TOXIC: Asbestos mineral. Never cut, grind, or disturb fibers. Handle sealed specimens only. Wash hands thoroughly. Keep away from children.
TOXIC: Contains mercury. Handle briefly, wash hands immediately. Display in enclosed case. Never heat or grind.
Durable (Mohs 6) but high birefringence can make the stone appear doubled - normal, not a flaw. Safe for mild soap and water. Avoid ultrasonic cleaning. Pamir origin commands premium - verify with documentation.
Soft (Mohs 3). Avoid water. Clean with dry cloth only. Handle carefully to preserve druzy crystal surfaces.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains water (up to 20%) like all opal. Avoid heat, dry environments, and sudden temperature changes. Can craze or crack if dehydrated. Display with backlighting to appreciate the transmitted-light play-of-color. Brief rinse only.
Organic gem. Avoid chemicals, perfume, ultrasonic cleaners. Clean with damp cloth.
Extremely soft (Mohs 1.5) with perfect cleavage. Tarnishes in air. Avoid water. Handle minimally.
Extremely fragile needle crystals. Display only. Handle by matrix. Even gentle contact can snap crystal tips.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Andradite garnet with lower hardness than most garnets (6.5). Higher dispersion than diamond (0.057). Avoid sharp impacts. Russian horsetail-inclusion stones have highest value - provenance matters. Safe for mild soap water.
Extremely fragile and water-soluble (selenite variety). Display only.
Extremely durable. Safe for ultrasonic cleaning. Avoid hard impacts along cleavage.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains copper minerals (malachite, chrysocolla, azurite, turquoise). Mildly toxic if ingested. Avoid water and gem elixirs. Clean with dry cloth only. Soft and porous (Mohs 5 average). Original mine closed 1985 - all material is legacy stock.
Avoid temperature extremes - trapped water can expand and crack the crystal.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
TOXIC: Contains cobalt and arsenic. Display only. Wash hands after handling. Never use for gem elixirs.
Perfect cleavage in one direction makes it fragile despite hardness 7.5. Avoid sharp impacts that could split the stone along the cleavage plane. Store separately from harder stones. Brief rinse fine, but don't subject to ultrasonic cleaning.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Quartz with natural etched windows on the faces. The interior surfaces of the windows are fragile features - avoid abrasive contact. Safe for water and mild soap cleaning. Handle by the base to preserve the window geometry.
Contains water like all opal. Avoid sudden temperature changes. Can crack from dehydration. More stable than Australian opal but still sensitive.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Perfect cleavage makes it fragile. Can fade in strong light. Avoid thermal shock.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Extremely fragile hollow tubes. Handle with extreme care. Many specimens break during transport.
Contains lead. Wash hands after handling. Keep away from children.
Nickel carbonate. Avoid prolonged water contact. Relatively soft (4.5). Clean with dry cloth.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Chemically inert and doesn't tarnish, but very soft (Mohs 2.5) and often on fragile matrix. Clean with a dry soft brush rather than wet handling.
Extremely durable. Safe for water, mild cleaners. One of the most resilient natural stones. Avoid only harsh acids on polished surfaces.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
DISSOLVES IN WATER. This includes selenite towers and satin spar. Never cleanse with water. Store in dry conditions. Extremely soft (Mohs 2).
Tenebrescent: color shifts with UV/sunlight and reverses in the dark. Direction depends on locality (some bleach in sun, some deepen). Not damage.
Quartz host is durable (Mohs 7). The iron-oxide platelet inclusions are stable and preserved indefinitely inside the crystal. Safe for water and mild soap cleaning. Avoid extreme heat which could affect lepidocrocite inclusions.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Can fade with prolonged UV exposure. Store away from direct sunlight. Has perfect cleavage - avoid impacts.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains trace amounts of naturally occurring uranium (very low levels). Safe for normal handling and display. Avoid prolonged skin contact and never grind or sand. Wash hands after extended handling. Its uranium content is what causes strong green fluorescence under UV light.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Durable (Mohs 8) but has perfect basal cleavage. Avoid sharp impacts. Safe for gentle cleaning.
RUSTS if exposed to moisture. Store with desiccant packets in sealed container. If surface shows orange rust spots, treat with gun oil or Renaissance Wax. Never submerge in water. Handle with clean dry hands.
Clean with dry or slightly damp cloth. Store away from harder minerals.
One of the rarest gem minerals. Hardness 7 with no special fragility. Safe for mild soap and gentle water cleaning. Value is such that secure storage matters more than care routine. Don't confuse with aquamarine (jeremejevite is heavier and more valuable).
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Opal-ironstone composite. The ironstone matrix stabilizes the opal veins but avoid prolonged water contact - ironstone can rust and opal can craze. Most cabochons are untreated. Avoid heat and dry environments.
Fades permanently in sunlight. Store in dark when not wearing. Evening stone only.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains arsenic. Display only. Wash hands after handling. Do not use for gem elixirs.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Soft and acid-sensitive like marble. Effervesces in vinegar. Avoid acidic cleaners. Fossils within may be fragile.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Copper content makes it toxic if ingested. Do not use for gem elixirs. Avoid prolonged water contact.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Soft (Mohs 3) and acid-sensitive. Avoid vinegar, lemon juice, and acidic cleaners. Stains easily. Clean with pH-neutral soap only.
Chemically unstable. Decomposes in humidity into sulfuric acid ('pyrite disease'). Keep dry. Store with desiccant packets. Inspect periodically for white powdery residue.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains lead and arsenic. Display only. Wash hands after handling.
Extremely durable (9.25 Mohs). Safe for ultrasonic cleaning. Nearly indestructible for jewelry.
Chalcedony (Mohs 7). Safe for mild soap and water. Vivid chromium green is stable. Distinguish from dyed green chalcedony (acetone swab test) and chrysoprase (nickel-colored, fluoresces under UV).
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
FLAMMABLE. Keep away from heat, flame, and sparks. Can crack from thermal shock (even body heat on cold specimens). Store at stable room temperature. Never heat. Wash hands after handling.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Toughest natural material. Virtually indestructible. Safe for water, mild soap. One of the most durable stones for jewelry.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
EXTREMELY fragile. Never touch crystal fibers - skin oils permanently mat them. Handle by matrix only. Store in protective display case.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains water (up to 20%). Avoid heat and dry environments. Can crack from dehydration.
Perfect cleavage in three directions. Avoid impacts. Clean carefully. Fascinating double-refraction demonstration piece.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Feldspar with copper inclusions. Perfect cleavage like all feldspar - avoid impacts. The copper schiller is stable under normal conditions but avoid acidic cleaners which can etch copper platelets. Brief rinse acceptable.
TOXIC: Contains arsenic. Light-sensitive. Store away from sunlight. Handle briefly, wash hands immediately. Never heat or grind.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Corundum durability (Mohs 9). Safe for ultrasonic and most cleaning methods. Verify beryllium-diffusion treatment status with GIA/SSEF/Gübelin certification - untreated Sri Lankan stones command the highest prices.
Durable (Mohs 8). Safe for careful handling. Extremely valuable - store securely in padded display.
Copper-bearing silicate, typically encountered as inclusions in quartz from Messina mine. Quartz host is durable but the papagoite inclusions may alter if the host is cracked. Avoid strong acids and ultrasonic cleaning. Original mine closed - provenance adds value.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Feldspar with perfect cleavage. Avoid hard impacts that could split along cleavage planes. Brief rinse fine. The peach color is stable under normal light. Store separately from harder stones.
Acid-treated surface may dull over time. Avoid water. Handle minimally.
Organic gem. Avoid chemicals and perfume. Wipe with soft damp cloth after wearing. Store separately.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Same care as amethyst. May fade with prolonged strong sunlight exposure. Durable for display and handling.
DISSOLVES IN WATER. Rock salt with delicate pink coloration. Never cleanse with water. Store in dry sealed container with desiccant packets - even humidity causes damage. Very soft (Mohs 2.5). Display only. Never use in elixirs or baths.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Extremely durable. Doesn't tarnish. Safe for water and mild soap cleaning. Virtually indestructible.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Durable (Mohs 7). Safe for water and mild soap. Morgan Hill type locality material has collector value - document provenance. Dyed imitations are common in tumbled stones - stick to verified sources.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
TOXIC: Contains arsenic. Darkens permanently in light. Store in complete darkness. Wash hands after handling.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Iron sulfide oxidizes when wet. Can develop sulfuric acid residue. Keep dry.
Contains copper silicate minerals (chrysocolla, malachite, shattuckite, dioptase). Mildly toxic if ingested. Never use in gem elixirs. Avoid prolonged water contact. Variable hardness (3-7 across component minerals). Clean with dry cloth.
Andradite variety (Mohs 6.5-7). The iridescence comes from internal structure and is permanent. Safe for mild soap and water. Avoid ultrasonic cleaning (interference lamellae can be stressed). Heat can affect iridescence intensity.
Extremely rare orthoclase from a single Northern Territory mine. Feldspar cleavage - avoid impacts. Brief rinse only. Store separately and securely given the provenance value. Ilmenite and hematite inclusions are stable under normal conditions.
Has feldspar cleavage. Avoid hard impacts. Brief rinse fine. Store separately from harder stones.
Clean with dry or slightly damp cloth. Store away from harder minerals.
TOXIC: Contains arsenic. Decomposes in sunlight into yellow powder. Store in complete darkness. Handle briefly, wash hands immediately. Display in enclosed case.
Durable (Mohs 7.5) but extremely valuable. Handle with care due to investment value, not fragility. Store securely.
Hard (Mohs 8) and durable, but the cubic/dodecahedral crystal form is the valuable feature - avoid impacts that could chip crystal edges. Pyroelectric - develops charge when heated, may attract dust. Safe for gentle water rinse.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Dissolves in water. Store dry. Clean with dry cloth only. Extremely soft (Mohs 2).
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Soft (Mohs 4.5-5) manganese silicate. Fragile prismatic crystals - handle by matrix only. Avoid water and ultrasonic cleaning. Fluorescent salmon pink under longwave UV. Original Mont Saint-Hilaire provenance essential for authenticity.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Copper silicate, relatively soft. Avoid prolonged water contact. Clean with dry cloth.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Tarnishes in air. Store in anti-tarnish cloth. Clean with silver polish.
Durable borate (Mohs 6.5). Safe for mild soap and water. Historically mistaken for peridot - documentation of RI/SG testing adds value. Avoid ultrasonic cleaning.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Very soft (talc-based). Scratches easily. Oil or wax can enhance and protect the surface. Do not use abrasive cleaners.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Corundum (Mohs 9). Safe for ultrasonic cleaning on verified natural stones. Glass-painted asterism fakes exist - check the star is on the dome, not the base. Linde synthetics have flawless stars but curved growth lines under magnification.
Contains antimony. Wash hands after handling. Extremely soft and fragile. Handle by matrix only.
Extremely soft (Mohs 1.5-2). Scratches with a fingernail. Avoid water and store away from harder stones. Handle gently - tumbled pieces are stable but raw specimens are delicate.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
The softest mineral (Mohs 1). Scratches with fingernail. Handle gently. Dust can be an irritant if inhaled. Clean with dry cloth only.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Color deepens in sunlight, fades in dark (tenebrescence). Strong UV fluorescence. Handle normally.
Porous. Absorbs oils and chemicals which change color. Avoid sunscreen, perfume, and soap.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Contains lead. Handle with care. Never use for gem elixirs.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Slender prismatic habit is more fragile than bulky amethyst clusters. Handle doubly-terminated floaters with care. Same sunlight sensitivity as all amethyst - prolonged sun exposure can fade the purple color.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Darkens irreversibly in light. Store in complete darkness to preserve color. Extremely soft and fragile.
Durable. Safe for cleaning with mild soap and water.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Very heavy and durable. Avoid prolonged water contact. Clean with dry cloth. The density can surprise you - handle securely.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.
Clean with dry or slightly damp cloth. Store away from harder minerals.