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Please be aware that clay is susceptible to freezing. We take precautions to monitor weather conditions at the shipping destination; however, we cannot guarantee protection against freezing temperatures during transit. Please plan your clay purchases accordingly.
Please be aware that our clay is susceptible to freezing. We take precautions to monitor weather conditions at the shipping destination; however, we cannot guarantee protection against freezing temperatures during transit. Orders shipped during cold weather may be exposed to conditions that could affect the quality of the clay. Please plan your clay purchases accordingly.
Gerstley Borate

Gillespie Borate

$105.00 - $105.00
$105.00
$105.00 - $105.00
$105.00

Gillespie Borate is a blended borate mineral used in ceramics, serving as a replacement for Gerstley Borate on a pound-for-pound basis.

Fluxing Agent: Improves glaze consistency, fluxing at low and mid-range temperatures, while enhancing surface smoothness.

Source of Boron: Provides a consistent source of boron, resulting in fewer impurities, brighter colors, and reduced issues like crawling and pinholes.

Serving as a replacement for Gerstley Borate on a pound-for-pound basis.

Sold in 50lb bags. The price above is price per 50lb bag. Enter the number of bags. Quantity break pricing will be applied at checkout.
1 bag= 50lbs, 2 bags= 100lbs, 4 bags= 200lbs

If purchasing 200lb+, call (405) 510-0076 or email office@mammothclay.com to order.