|WikiProject Chemistry||(Rated Start-class, Low-importance)|
|WikiProject Color||(Rated Start-class, Low-importance)|
This article seems inaccurate. The madder root ("crushed" or not) is basically colorless, and the alizarin/purpurin dye needs to be chemically extracted from it. The oil paint is probably madder lake, a combination of alizaring and metals. The qualifier "genuine" sounds like a commercial product plug. This article needs to be checked by an expert. All the best, --Jorge Stolfi (talk) 00:27, 30 January 2010 (UTC)
- I have tried to fix the definition. According to the body of the article, this seems to be indeed an alizarin lake, and Alizarin Crimson is basically a synonym. --Jorge Stolfi (talk) 01:23, 30 January 2010 (UTC)
- "Madder Lake" is the name of the natural lake pigment containing both alizarin and purpurin and derived from the madder plant. "Alizarin" is one of the dyes in the madder plant but when used as a term on its own generally indicates an artificially produced pigment (since the natural pigments are not pure alizarin, also containing purpurin). "Rose madder" is a commercial name traditionally used for paints made from madder lake pigment. Please see my suggestion below for renaming the article because of issues like this. Autumnalmonk (talk) 00:52, 3 February 2010 (UTC)
Article is incomplete
There are still many questions, e.g. what is the chemical composition (aluminum salt?), when was it invented, etc. Also some of the statements seem subjective or painter folklore. All the best, --Jorge Stolfi (talk) 01:23, 30 January 2010 (UTC)
- I'll agree that this article has several issues. I've attempted to add more factual data and references along the lines of what was already present. I also agree that some of the "painter folklore" and commercial material needs to be cut, and I'll begin doing so. I think that changing the article name (see below) will help clarify the focus of the article and assist in tightening it up. Autumnalmonk (talk) 00:58, 3 February 2010 (UTC)
- I've just finished a major article clean-up. I started addressing some of the most obvious issues, but one thing led to another and in the end it has turned out to be a nearly complete overhaul. I think what we have now is a well organized and well referenced article. Let me know what you think. Autumnalmonk (talk) 11:11, 3 February 2010 (UTC)
The following statements had better be removed until a reliable source is found:
- Rose Madder is not toxic.
- Rose Madder is believed to be more permanent than Alizarine Crimson.
Rename article "Madder Lake"?
(continued from the discussion page of Alizarin) - "Rose Madder" is a common commercial name of some varieties of paint made from the pigment "Madder Lake". Currently Madder Lake redirects to Alizarin, which it should probably not as the two, while related, are NOT the same thing. I think it would be much more appropriate to rename this article Madder Lake, remove the redirect from "madder lake to Alizarin, and set up a redirect for "Rose Madder" to the (newly renamed) Madder Lake. Autumnalmonk (talk) 00:40, 3 February 2010 (UTC)
- Seems like a good plan. However since "madder lake" is a generic name for a vaguely defined substance (madder dye chemically combined with some metal like calcium or aluminum) it should be in lower case, like "alizarin" or "calcium chloride". On the other hand, I don't know wether it is intentional, but many articles for oil painters' pigments and industrial dyes it seem to use capitalized names, such as "Rose Madder", "Malachite Green", "Alizarine Cyanine Green G", etc. I don object to that capitalization "standard", but it should not be used outside its domain.
Actually, I am a "splitter" by temperament, and my instinct would be to have a separate article for each distinct concept: alizarin, purpurin, [new] "madder dye" (the natural dye extracted from the roots), [new] "madder lake" (the generic pigment class), Rose Madder (the classical artists' pigment, a particular instance or subclass of madder lake), [new]"Alizarin Crimson (pigment)" (the artists' pigment that is a synthetic replacement for Rose Madder), and alizarin crimson (color) (a particular shade of the color red, that could be refracted on a prism for the occasion, even if it is not as superintelligent as a certain particular shade of the color blue 8-) In my experience such splitting gives each article a well-defined focus and helps editors organize its contents in a logical order. On the other hand, it looks like some of those articles would be rather short, at least for the time being. All the best, --Jorge Stolfi (talk) 11:08, 3 February 2010 (UTC)
- I'm not a stickler for capitalization protocol as long as it stays consistent throughout the article. I come from an artist/pigment background so I capitalize by default but if someone wants to change it I'm not fussed. I can see splitting into all the different pages you mention, with the exception of "madder dye" as that is covered pretty well on madder. I think "Rose Madder", if restricted to not repeating what would be in "Madder Lake", would only have a few sentences that could be said about it. I'm not experienced in dealing with changing names and redirects, so I'll leave that up to someone else to sort out. Autumnalmonk (talk) 11:20, 3 February 2010 (UTC)
Because it is causing a Checkwiki error #72: "ISBN-10 with wrong checksum", I removed the ISBN from the entry: