That antimony trisulfide mix is very white but still pretty cheap:
64% potassium nitrate
18% sulfur
14% antimony trisulfide
4% dextrin
Electric Magenta is also very beautiful but still made of pretty cheap chemicals, though the composition is more complex:
38% strontium nitrate
8% potassium perchlorate
18% parlon
12% magnalium <74µm
10 copper carbonate
5% charcoal, airfloat
5% sulfur
4% dextrin
Most of the chemicals there are
pretty cheap, at least in comparison with the excellent colour you get.