Crystals

Professional buyers must verify the origin and growth method. Natural crystals should come with GIA or local gemstone laboratory certifications to prove they are not 'lab-grown.' Synthetic crystals (like hydrothermal quartz) have the same chemical properties as natural ones but lack natural inclusions. Imitations are often K9 glass or lead crystal, which can be identified by refractive index tests and the presence of air bubbles under magnification.

For decorative crystals, focus on the 4Cs (Color, Clarity, Cut, and Carat weight). Ensure the Mohs hardness scale rating matches the specific mineral (e.g., Quartz is 7). For industrial or healing crystals, transparency grades (AAA to B) and the absence of heavy metal leaching (especially for 'crystal' glassware containing lead) are critical compliance factors.

When purchasing carved or polished items, specify the polishing grit level (e.g., 3000+ for a mirror finish) and dimensional tolerance (typically ±0.5mm for jewelry beads). For 'Aura' or coated crystals, inquire about the vacuum deposition (PVD) process to ensure the metallic coating does not peel or fade over time.

Request documentation regarding Social Accountability (SA8000) to ensure no child labor was involved in mining. Verify that the supplier follows environmental regulations for wastewater treatment, especially if they perform acid washing or chemical dyeing to enhance crystal color.

The biggest risk is cleavage or fracturing due to thermal shock or rough handling. Insist on multi-layer packaging: individual bubble wrapping, double-walled corrugated boxes, and vacuum-sealed bags to prevent friction. For high-value shipments, use wooden crates and ensure the Incoterms are CIF (Cost, Insurance, and Freight) to cover potential transit damage.

Start by requesting a pre-shipment sample or a high-definition video inspection of the specific batch. Negotiate based on weight (kg) for raw stones and unit price for finished carvings. Ask for a tiered pricing structure where the price drops by 15-20% when moving from 'sample' to 'wholesale' volumes (e.g., >100kg).

Check the HS Code (typically 7103 for precious/semi-precious stones) to determine import duties in your country. Be aware that some countries have restrictions on 'conflict minerals' or specific mining regions. Ensure the Commercial Invoice clearly states if the crystals are natural or synthetic to avoid customs seizures or misclassification fines.

Always use Secured Trading Services provided by platforms like Made-in-China.com to hold payments in escrow until the goods pass inspection. For large orders, hire a third-party inspection agency (like SGS or Intertek) to perform a Random Sampling Inspection at the supplier's warehouse before the final balance is paid.