Soda Feldspar

ceramics / materials / ctm / soda-feldspar

Source: http://ctmpotterssupplies.co.uk/ceramicmaterialsglossary.html

Na2OK2OAl2O3SiO2LOI
  8.50  2.80 18.5  69.5   0.70

From CTM Website:

K2O 2.8%, Na2O 8.5%, Al2O3 18.5%, SiO2 69.5% typical More suitable feldspar for lower temperature glazes.