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EP Kaolin
Plastic White Firing Kaolin
Chemistry
Chemistry available on new site, see link above
Mineralogy
- Kaolinite: 97%
Links to Other Materials
- Pioneer Kaolin - Alternative
- Edgar Glass Sand - Related
- Kaolin - Parent
- Cache
Hazards
- Kaolin
Miscellaneous
- Family: Kaolin
- Region: North America
- Mined At:
- Raw Mineral: No
- Generic: No
Notes
A secondary water washed kaolin mined in Florida. It is fairly plastic and very white firing compared with most other American kaolins. It has excellent casting properties. It is not plastic enough for throwing bodies, thus it should be augmented by a more plastic kaolin or by a plasticizer like bentonite or hectorite.
EPK is considered by many to be the best North American kaolin for use in suspending glazes as it tends to produce a smooth thixotropic slurry. 15-20% will normally make the glaze gel slightly, thus when a piece is immersed in the slurry and removed it drips very little and the wet glaze layer stays in place for the time it takes to dewater. Since EPK is very close to theoretical kaolin chemistry, it will subsitute for any other kaolin that can make the same claim (e.g. Pioneer).
This material is mined and processed in Edgar Florida. It is extracted hydraulically (a high pressure stream of water is used to wash the clay/sand mix from the bank into a small lake). The slurry is pumped from the bottom and transported to vibrating screens that separate out the sand and grade it into sizes. The clay that passes the screens is pumped into a pond and settled with the aid of a flocculant. The slurry is then dried and the flocculant neutralized. The main product at this mine is high quality white sand, the clay is a byproduct. The company is confident that there are reserves for the next hundred years or more and the quality will be constant throughout the life cycle of the deposit.
Data
- Apparent Viscosity (cps): 1.35
- Bulk Density (lbs/cu. ft): 32.4 loose, 46.2 tapped
- pH: 5.8 at 10% solids
- Specific Gravity: 2.5
- Surface Area (m2/gm): 24.25
- Drying Shrinkage: 5.8%
- Apparent Viscosity (cps): 6000 @ 35% solids (wt.)
- Water of Plasticity: 26%
- Sieve Analysis Wet
+60 mesh: 0%
+80: 0%
+100: 0.1%
+200: 0.8%
+325: 1.5%
- Dry M.O.R.: 300 psi
- C.E.C.: Methylene Blue: Acid Treated-5.2 Meq/100 gm
- Ultimate Particle Size Distribution
40 microns: 100%
10: 90%
5: 78%
3: 68%
1: 49%
.5: 40%
.2: 20%
- Water absorption
Cone 11: 11.3% - Firing Shrinkage
Cone 11: 11.6% - Alkali Reponse: 5.8 Meq/100 gm
- H2O2 Reaction: 6.5 Meq/100 gm
URLs
- Data Sheet - http://www.zemex.com/minerals/epk.html
- Another data sheet - http://www.zemex.com/feldspar/epk.html
Suppliers
- Feldspar Corp.
Authors
- Tony Hansen (Owner)
XML
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