You get what you pay for…..
Do you know what is in your paint, and are you getting what you pay for?
I often say “Paint is cheap”! It may not seem like it sometimes, but you really do get what you pay for. Back in the day, ultramarine blue was believed to be the most expensive colour, more pricey than even gold due to it being made from the semi-precious stone Lapis Lazuli from Afghanistan. You can actually still buy it through Kremer Paints for about $890 USD for 1 kg.. Luckily we have a synthesized French Ultramarine to take its place. A lot has changed since oil painting first began. These days we are lucky to have so many more resources and science and history on our side.
In the art stores you will notice professional level supplies have a variety of prices, even though the tubes are all the same volume. The reason being there are different amounts of pigments in the tube and those pigments varying in price. For example: You often see student grade paints like Winton, by Winsor and Newton (inventors of the commercial paint tube), paced the same across the board*. Well how do they do that? Balance it out with a loss on some and a gain on others. Maybe a bit? The exception to the rule is Cadmium pigments, which cost way more in general and they tend to be twice the cost. So to do it, they mainly reduce the amount of pigment in the tube and fill it with other additives and fillers.
Another way to judge the quality of paint is to feel the weight of the tube of paint. Higher quality paints and pigments are on average much heavier for the same amount of volume because the ration of pigment particles to vehicle is higher. Companies like Rublev, Micheal Harding and Williamsburg have much more high quality to pigment to vehicle ratio and little to none of the fillers, waxes, resins or binding agents that make inferior quality products. There is a caveat, new pigments with scientific chemical names tend to be lighter than their heavier mineral counterparts.