G2826X - Randy's Red Cone 5
Modified: 2022-08-04 22:32:31
A popular Gerstley Borate based iron-red glaze.
| Material | Amount |
|---|---|
| Silica | 29.70 |
| Kaolin | 5.00 |
| F-4 Feldspar | 19.80 |
| Talc | 13.90 |
| Gerstley Borate | 31.70 |
| Added | |
| Red Iron Oxide | 15.00 |
| Bentonite | 2.00 |
| 117.10 | |
Notes
There is much more information about this glaze at http://gerstleyborate.com.
The Boraq Gerstley Borate substitute works well in this recipe.
Related Information
Iron Red glazes look a little different in a flow tester

This picture has its own page with more detail, click here to see it.
A GLFL test for melt flow comparing two cone 6 iron red glazes fired to and cooled quickly from cone 6. Iron reds have very fluid melts and depend on this to develop the iron red crystals that impart the color. Needless to say, they also have high LOI that generates bubbles during melting, these disrupt the flow here.
G2896 Ravenscrag Plum Red iron red cone 6 glaze

This picture has its own page with more detail, click here to see it.
Original development of the G2896 recipe was done to match the chemistry of Randy's Red (a popular recipe). At the time we did not do any special firing schedule to encourage the growth of the red crystals.
Randy's Red cone 6 iron red glaze

This picture has its own page with more detail, click here to see it.
Links
| Materials |
Boraq
This Gerstley Borate substitute was available during the early 2000s. Its recipe and development are well documented but two materials are no longer available. |
| Glossary |
Iron Red Glaze
A type of ceramic glaze, typically fired around 2200F, where iron oxide in the cooling glass precipitates out to form a striking red crystalline mesh on the surface. |
| Recipes |
G2896 - Ravenscrag Plum Red Cone 6
Plainsman Cone 6 Ravenscrag Slip based iron-red glaze. It can be found among others at http://ravenscrag.com. |
XML to Paste Into Insight-live
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Randy&#039;s Red Cone 5" keywords="A popular Gerstley Borate based iron-red glaze." id="63" date="2022-08-04" codenum="G2826X"> <recipelines> <recipeline material="Silica" amount="29.700"/> <recipeline material="Kaolin" amount="5.000"/> <recipeline material="F-4 Feldspar" amount="19.800"/> <recipeline material="Talc" amount="13.900"/> <recipeline material="Gerstley Borate" amount="31.700"/> <recipeline material="Red Iron Oxide" amount="15.000" added="1"/> <recipeline material="Bentonite" amount="2.000" added="1"/> <url url="https://digitalfire.com/recipe/63" descrip="https://digitalfire.com/recipe/63"/> </recipelines> <urls/> </recipe> </recipes>