In 2012 the popular pigment PY153 Nickel Dioxine Yellow was discontinued, no doubt because of lack of demand from the chemical and/or auto industries. As has been pointed out previously makers of watercolour or other types of paint are very much at the bottom of the pile and have to take whatever is available. Although not offered by a huge number of paint makers PY153 was the pigment used by both Winsor & Newton and Daniel Smith for the popular New Gamboge paints. Both have already reformulated with a multi pigment mix. In addition Rowney and one or two others called it `Indian Yellow, supposedly a replacement for the notorious original Indian Yellow. Why notorious? It has been said, and repeated many time, that this paint was made in a vile process by feeding cows in India with certain types of leaves, that turned their urine yellow, and this was the foundation of the paint. Although this story has been repeated many times I, in my capacity as a (very) amateur historian, researched the story and discovered that it might all be nonsense with no real basis in fact.
The Rowney Indian Yellow is a staple in my palette so I have to decide at some stage on a replacement. I still have a full tube so this isn't urgent. Handprint claims several orange-yellow and yellow-orange paints make adequate replacements but basically plumps for three, PY35, PY65 and PY110. Before I continue you will find that several paint suppliers still list PY153 and may continue to do so. Can you trust the labelling? Possibly but I have my doubts and in fairness one can't expect a manufacturer to immediately change the labelling for just a single paint. I notice that Winsor & Newtons new style bare metal tubes appear to have the information printed on them so that may mean they can change details quite rapidly. Winsor & Newton have also said that their usage of pigments is so large that, when a pigment is discontinued, they run out quite rapidly.
The left swatch is Indian Yellow from Rowney. The two middle swatches are Permanent Yellow Deep (PY139) from Maimeri and Venezia respectively, while the right one is Cadmium Yellow Light ((PY35) from Lukas. The closest appears to be the Lukas paint but, being a Cadmium, is opaque and also toxic. The two Maimeri paints appear more orange. Neither PY65 or PY110 are (as yet) widely available but PY65 is listed by W & N as Winsor Yellow Deep, also by DaVinci as Hansa Yellow Deep and Arylide Yellow Deep. Daniel Smith call it Hansa Yellow Deep. So far PY110, which is highly praised by Handprint, is only on offer from Daniel Smith and Graham - Permanent Yellow Deep - Indian Yellow respectively. This may change in the medium to long term.. Daniel Smith call PY108 Indian Yellow.
What to do? I don't have to change immediately so will ponder the problem for a while. My inclination is to try PY110 maybe from Daniel Smith. Any corrections or additions to the above are welcome and can be incorporated in the text.