We have added granular Manganese Dioxide to our RO-30 to give it a "reduction" look . The speckles will "bleed" through a clear or opaque glaze.
% Shrinkage
C/06=7.0 C/1=10.2 C/6=11.7 C/10=13.3
%Absorption
C/06=10.4 C/1=4.0 C/6=2.0 C/10=0.7