Wednesday, February 10, 2010

Changes in the feldspar scene!

Soda Feldspar - Kona F4
There is a supply change in the Soda Feldspar Kona F4. It is not available from the mine any longer due to a fire and mine closure. We will have Minspar 200 available. They are both very close to the F4 in composition. A chemical analysis of the materials is below. (Download data sheet)

Minspar 200 Feldspar

Kona F-4 Feldspar   Sodium Feldspar

CaO 1.50

CaO 1.70


MgO 0.05

K2O 4.10

K2O 4.80

Na2O 6.50

Na2O 6.90

Al2O3 18.50

Al2O3 19.60

SiO2 68.60

SiO2 66.80

Fe2O3 0.06

Fe2O3 0.04

Volatiles % LOI 0.30

Volatiles %  LOI 0.20
                        Minspar 200 was Formerly NC-4 Feldspar.

G200 update From Jeff Zamek Article from Ceramics Technical (November 1, 2009)     (download G200 HD data sheet)

“G-200 felspar, mined by Imerys North America Ceramics, has been discontinued. While there are still stocks in potters' studios and ceramics supply bins it will eventually join Albany Slip, Gerstley borate, Kingman felspar, Oxford felspar, and other materials that have gone out of production. G-200's demise is based on economic considerations that potters do not control. Originally, G-200, as potters know it, was blended at the processing plant by using 70% Minspar 200, a sodium based felspar, and 30% HP G-200, a potassium based felspar. The blended felspars then became G-200 and were shipped throughout the United States.
The increasing costs of shipping Minspar 200 from Spruce Pine, NC and G-200 HP, mined in Siloam, GA, to the processing plant in Monticello, GA, a trip of over 200 miles, made this situation uneconomical. Potters are now faced with either using Custer feldspar in place of or finding a new potassium based felspar.”

Thank you Mr. Zamek I couldn’t have said it better or at all!

Laguna Clay will be blending G-200 so it will be available. G-200HP is the new product and according to Jon Pacini from Laguna the major difference is slightly more fluxing power, similar to (the also defunct) Kingman Feldspar of old.