Silica Glass Microspheres (Fused Quartz)
Synthetic fused silica glass microspheres ranging from 1 to 20 microns, used in semiconductor polishing slurries. Per chapter note 5, 'glass' includes fused quartz and other fused silica, and the diameter is under 1 mm, so they fall under tariff item 7018.20.00.
Import Duty Rates by Country of Origin
| Origin Country | MFN Tariff | Surtaxes | Total Effective Rate |
|---|---|---|---|
| 🇨🇳China | Free | — | Free |
| 🇲🇽Mexico | Free | — | Free |
| 🇺🇸United States | Free | — | Free |
| 🇩🇪Germany | Free | — | Free |
| 🇯🇵Japan | Free | — | Free |
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 the microspheres are pre-mixed with chemical polishing slurries
If the microspheres are part of a prepared chemical slurry, the mixture could be classified as a chemical product, but as standalone microspheres they remain in 7018.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right tariff item — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Confirm that the fused silica meets the definition of 'glass' under chapter note 5, which includes fused quartz
• Provide a technical datasheet showing the particle size distribution to verify the under-1-mm diameter
• Ensure the microspheres are not mixed with polishing compounds that could change classification
Related Products under Tariff item 7018.20.00
Aluminosilicate Glass Microspheres for Shot Peening
Precision-graded aluminosilicate glass microspheres ranging from 45 to 90 microns in diameter, used for shot peening aerospace turbine blades. These microspheres are under 1 mm in diameter and are not worked beyond the annealing stage, making them classifiable under tariff item 7018.20.00.
Borosilicate Hollow Glass Microspheres Type A
Hollow borosilicate glass microspheres averaging 30 to 120 microns in diameter, used as lightweight fillers in syntactic foams for aerospace composites. These microspheres are under 1 mm and are not further worked, qualifying for tariff item 7018.20.00.
Conductive Silver-Coated Glass Microspheres
Glass microspheres with a vacuum-deposited silver coating, ranging from 40 to 80 microns, used in conductive adhesives and electronics. The silver coating does not change the primary glass microsphere classification, and the diameter is under 1 mm, so they fall under tariff item 7018.20.00.
Expandable Glass Microspheres K15/250
Pre-expanded borosilicate glass microspheres ranging from 10 to 250 microns in their delivered state, used as fillers in thermoplastics. These microspheres are under 1 mm in diameter and are not further worked, making them classifiable under tariff item 7018.20.00.
Fluorescent Glass Microspheres for Tracers
Polystyrene-core glass microspheres with fluorescent doping, ranging from 10 to 50 microns, used for flow visualization in scientific research. Despite the polystyrene core, the outer glass layer and the under-1-mm diameter place them under tariff item 7018.20.00.
High-Index Glass Microspheres for Reflective Paint
Spherical glass microspheres with a refractive index greater than 1.9, ranging from 100 to 300 microns, used for retroreflective highway markings. These microspheres are under 1 mm in diameter and are not coated with a reflecting layer as defined in chapter note 2, so they fall under tariff item 7018.20.00.