Sheffieldpottery New Zealand Halloysite Kaolin 55 pounds dry

Product details

Technical Overview

New Zealand Halloysite Kaolin Full Bag : 55 pounds dry From Digital Fire: New Zealand China Clays claim that this is the whitest clay in the world. The white primary clay deposits mined at Matauri Bay are derived from the alteration of acid volcanic rocks. The aluminosilicate feldspar minerals in the parent rhyolite have been broken down to their constituents by low temperature hydrothermal alteration and have then reconstituted as halloysite. Thus, while often called a kaolin, technically it is a halloysite. The company has developed a unique beneficiation process (which includes filter pressing and thus the designation PFC or Premium Filter Cake) to ensure a high degree of purity for this New Zealand halloysite kaolin. They claim 0.1% on a 240 mesh screen This kaolin material is exported to many parts of the world. Small scale users have found it a little whiter burning than Grolleg Kaolin. It also supports translucency better. As a pure material, NZK is much less plastic than pure Grolleg (being barely plastic enough to wedge and roll into a slab, for example). However Grolleg requires about the same amount of bentonite (or VeeGum) compared to NZK to create a porcelain of the same plasticity. This New Zealand halloysite kaolin responds especially well to VeeGum to create very plastic porcelains that still dry very well.