Epsom salt

Buyers must distinguish between Technical Grade, Agricultural Grade, and Pharmaceutical/Food Grade (USP/BP/FCC). For personal care or food applications, ensure a purity level of ≥99.5%. Key chemical markers include Magnesium (Mg) content (typically ~9.8%) and Magnesium Sulfate (MgSO4) content (≥48% for heptahydrate). Pay close attention to particle size (granularity), ranging from extra fine to large crystals, depending on whether it is for rapid dissolution in baths or slow-release in fertilizers.

For the US market, USP (United States Pharmacopeia) grade is essential for health and beauty products. In the EU, compliance with REACH regulations and E518 food additive standards is required. If sourcing for agriculture, look for ISO 9001:2015 quality management certifications. Always request a Certificate of Analysis (COA) and a Material Safety Data Sheet (MSDS) from the supplier to verify heavy metal limits (such as Arsenic <2ppm and Lead <1ppm) are not exceeded.

Epsom Salt is most commonly traded as Heptahydrate (MgSO4·7H2O), which contains about 51% water. Anhydrous Magnesium Sulfate is more concentrated and expensive but reduces shipping weight. Buyers should calculate the cost per unit of active Magnesium rather than just the gross weight. Note that Heptahydrate is prone to caking (clumping) if stored in humid conditions, so specify anti-caking agents or moisture-proof PE/PP laminated packaging for long-distance sea freight.

Epsom salt is sensitive to temperature fluctuations and humidity. Ensure the supplier uses double-layered packaging (inner PE bag + outer woven PP bag). For bulk shipments, request container liners to prevent moisture ingress. It is highly recommended to use Made-in-China.com's Secured Trading Service to ensure that payment is only released after a third-party pre-shipment inspection (such as SGS or BV) confirms the salt is free-flowing and meets chemical purity specs.

Since Magnesium Sulfate is a commodity, prices fluctuate with raw material (Magnesite/Sulfuric Acid) costs. Negotiate based on tiered pricing (MOQ vs. Full Container Load). Professional buyers often secure a 5-10% discount by committing to an annual volume while requesting staggered shipments. Ask the supplier if they have export tax rebate qualifications in China, as this can often be leveraged to lower the FOB price.

When shipping to the US or Europe, ensure the HS Code (typically 283321) is correctly declared to avoid customs delays. Because it is a chemical product, some carriers may classify it under 'General Chemicals'; always provide the MSDS in the destination country's language. For shipping from China, Qingdao and Tianjin ports are primary hubs for chemical exports; choosing a supplier near these ports can significantly reduce inland trucking costs.