Artist grade paints labeled as Viridian are made using Hydrated Chromium Hydroxide (labeled as PG 18 on tubes). It is a specialty pigment, one that is not produced in the same quantities as the Phthalo colors, and likely carries a big price tag. And since about half of a tube of Viridian Green is pigment, presumably this is why Viridian is often one of the highest priced paints in a brand.
For Gamblin Oil Paints, a 32 ounce can of Viridian comes out to about $7.18 per ounce. For those of you using a more normal quantity, a 150ml tube (about 5 ounces) comes out to $9.45 per ounce. Compare that to Gamblin’s black and white colors which cost about $4 to $5 an ounce in their 150ml tube size.
While the prices for specialty chemicals, metals, such as Hydrated Chromium Hydroxide are not generally publicly known and are seen as a kind of trade secret by those who do know… we do know that it is becoming increasingly difficult to find a single manufacturer, let alone multiple to offer cost competition, for a number of specialty chemical / pigments / metals. Even Titanium White, a color widely used in an array of products, is currently having price increases across all quality grades.
Another example, one of the last makers of an Antimony based yellow stopped producing it over a year ago leaving the world without ANY source. Even the Pentagon has just realized that a surprisingly large number of the specialty chemical products necessary for normal operations either only have a single manufacturer or are discontinuing making the product… leaving no producer left on the entire planet.
We live in a changing world and as a society have yet to realize the importance of a lot of the specialty chemicals, pharmaceuticals, and metals that make modern life possible.