Fire Assay Cupels

Westref’s are used to heat and separate gold and other precious metals from base metals in the fire assay process. Manufactured to exacting standards under ISO Guide 9001, the cupels can be produced in a range of custom sizes and to suit your specific testing and purity needs. Our magnesia cupels are made from world-class raw materials and can withstand extreme temperature shocks, offer reliable levels of lead absorption and produce consistent results with low losses. Westref offers a wide variety of sizes of fire assay cupels to fit your mineral laboratory’s needs. Our cupels are packaged securely in a nested fashion to allow for efficient use of space in shipping and storage. See why Westref is fast becoming a trusted global name in the mining and geochemical lab market.

  • Manufactured to exacting standards under ISO Guide 9001
  • World-class raw materials
  • Consistent results and low losses
  • Custom sizes available

Available Magnesite Products

  • Magnesite Cupels
  • Bullion Blocks
  • Furnace Powder

Available Cupel Sizes

All standard sizes are available:

List of Fire Assay Cupel sizes available to order.

Custom sizes available on request.

What are Fire Assay Cupels?

Cupels are vessels made out of magnesite, bone ash or other materials which are used in the fire assay process to isolate the precious metals. Their porous nature allows them to be used to absorb base metals and impurities through a process of oxidisation. The precious metals being tested, due to their chemical nature, do not oxidise and remain on top of the cupel surface in a metallic bead known as a prill. Cupels are a critical part of the fire assay process, allowing metallurgists to reliably separate and measure the amounts of precious metals present in mineral samples. Not all magnesite is appropriate to produce cupels, so talk to Westref and be sure to get the right product, first time.


“Reliable, driven, family business that provides quality products and will work diligently with its partners towards mutual success.”

Anonymous customer survey submission, 2016

“I hope you can keep producing such wonderful products and expand the range of your products”

Head of Fire Assay

“We have been using Western Refractories Fire Assay Flux, Crucibles and Cupels for the past six years at our Laboratory in Metro Perth and have had virtually no issues with the quality of the products or timely supply.”

Laboratory Manager Perth, Western Australia

“WR’s level of support, commitment to partnering, response time and desire to constantly improve are exceptional.”

Procurement Lead Perth, Western Australia
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