Warning: This pigment is extremely lightweight and prone to dusting, so please follow all safety instructions provided on the label. When incorporating this material into concrete or cement, it is only appropriate for interior applications. Additionally, do not treat the finished surface with hydrochloric acid. Chemical description: Azomethine-Copper complex. Pigment Yellow 129, C.I. 48042 Resistance to alkali: 5 (1 is bad, 5 is best) Resistance to lime: 5 (1 is bad, 5 is best) Resistance to acid: 5 (1 is bad, 5 is best) Lightfastness - thinned: 7-8 (1 is bad, 8 is best) Lightfastness - medium: 8 (1 is bad, 8 is best) Lightfastness - concentrated: 8 (1 is bad, 8 is best) ColorIndex: PY 129.48042 Suitability: Acrylics, Cement / Tadelakt, Lime / Fresco, Oil, Tempera, Violin Varnish /Wooden Surfaces, Watercolor / Gouache