Volcanic Sulfur Crystals
Bright yellow crystalline sulfur formed around volcanic fumaroles, hand-collected with minimal processing. Classified in HTS 2503.00.00 as crude natural sulfur excluding the prohibited sublimed, precipitated, and colloidal forms.
Import Duty Rates by Country of Origin
More Specific Codes
This product may fall under a more specific subheading:
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If artificially sublimed
Chapter explicitly excludes sublimed sulfur from 2503.
If mixed with other earth minerals
Mineral mixtures with low sulfur content may classify under 2530 as earth colors or chlorites.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right HTS code — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Include photos or affidavits of volcanic origin to support crude classification
• Declare any adhering volcanic ash separately to prevent mixed-material disputes
Related Products under HTS 2503.00.00
Crude Natural Sulfur Ore
Raw sulfur extracted from volcanic deposits or natural underground formations, containing impurities like soil and moisture. It falls under HTS 2503.00.00 as crude sulfur of natural origin, excluding processed forms like sublimed, precipitated, or colloidal sulfur as specified in chapter notes.
Native Lump Sulfur
Large irregular lumps of elemental sulfur mined from caprock deposits, unrefined and suitable for crushing. Classified in 2503.00.00 as natural sulfur not subjected to sublimation, precipitation, or colloidal processing.
Frasch Process Sulfur
Molten sulfur extracted via the Frasch hot-water mining method from underground deposits, solidified into blocks. It qualifies under 2503.00.00 as natural sulfur, distinct from chemically precipitated or sublimed varieties.
Recovered Sulfur from Sour Gas
Elemental sulfur recovered as a byproduct from natural gas desulfurization plants via Claus process, in flake or prill form. Falls under 2503.00.00 as it remains unprocessed natural sulfur, not sublimed or colloidal.
Bulk Crushed Sulfur Rock
Crushed rock containing native sulfur from mining operations, used directly in sulfuric acid production. Meets 2503.00.00 criteria as unrefined sulfur not in excluded chemical forms.
Natural Sulfur Prills
Small spherical prills of native sulfur formed during natural cooling from molten extraction, minimally processed. Properly classified under 2503.00.00, distinct from artificially precipitated sulfur.