Maybe the orange worked particularly well for this technique!
Monart did use that technique in three (that I know of) different colour codes.
Gary
After some research I will have to amend my above statement.
The following Monart colour codes have this type of technique- 24 with orange and possibly blue, 143A orange, 261 orange, 261A orange and blue, 384 orange, 295A orange and blue, 395 orange, 396 orange and 455A orange. I have a bowl with orange and yellow (no colour code so far), the Perth museum lampshade orange (no colour code so far), ex I Turner collection Christies sale lot 100 KB bowl amber (no colour code so far).
This technique was used in Monart more than I originally thought, though still fairly uncommon.
Orange does appear to be the most used colour.
Gary