Chemical Analysis: 43% B²O³, 26% CaO, 4.5% SiO²
Hazard Symbol: HARMFUL
Variety or Brand: N/A
Pack: 500g

A powerful flux in glazes introducing an insoluble form of boron. Quantities greater than 5% will cause crawling and should be substituted with Gillespie Borate or Calcium Borate Frit.

Note:  Gillespie Borate is the recommended replacement for Gerstley Borate, which is no longer available.

We endeavour to despatch pallet and courier/post orders received by 11am the same day, stocks allowing.  At extremely busy times when receiving a high volume of orders, this may not be possible.
As we offer a great variety of products, ranging in size and weight we despatch our orders by the most suitable means for each order.  Our web shop offers express and budget delivery options.

Saturday deliveries can be arranged but incur a surcharge.  For this service please call 01243 265845.