2 different recipes. Brands sell different pigment mixtures under this name, so they won't all look or mix alike. Compare the pigments below; the most common is PB15 Phthalo Blue + PB29 Ultramarine Blue.
Who makes it
PB15 Phthalo Blue + PB29 Ultramarine Blue2
- Rembrandt Artists' Oil Colour No. 512PB29 PB15LF I Semi-opaqueSeries 2Hue15 ml tube · 40 ml tube · 60 ml tube* · 150 ml tube*About Rembrandt
PB29 Ultramarine Blue2
- PB29LF I Semi-transparentSeries 1Hue20 ml tube · 40 ml tube · 60 ml tube · 200 ml tube* · 500 ml tin*About Royal Talens
Sizes are the ones each line is sold in; marks a size only some colors come in. Check the store for a particular color.