- Hello, and thank you for your letter. No, they are not at all the same
thing. Soldium alginate is a pretty poor substitute for carrageenan, and I
don't know any professional marblers who use it. It might work for the more
marble-like, random patterns, but it would not do well for the fine-combed
feathery patterns. I know, carrageenan is ridiculously expensive, but
marblers have been looking for a cheaper substitute for a thousand years now
and haven't found anything yet that works as well. Some use methyl
cellulose, which is a bit cheaper, but still it doesn't work quite as well as
Galen at _MarbleArt.us_ (http://marbleart.us/)
In a message dated 4/15/2012 9:49:53 P.M. Central Daylight Time,
Is Sodium Alginate the same thing as Carrageenan? Dharma Trading sells
both.The Sodium alginate (sea weed) is so much cheaper.
[Non-text portions of this message have been removed]
- HI Joan,
Depending on the method of marbling that you are attempting, sodium alginate may suit your purposes. Some people I know have used it as a size for marbling with oil colors. If you're using acrylics, you can use hydroxypropyl methyl cellulose (HPMC) as well. Galen is right that it will not produce as fine a line as carrageenan size, but you have to ask yourself what your needs and goals are.
Personally, I've found that a 1:1 mix of Dow "J" grade cold-water dispersible "Methocel" HPMC and carageenan works well with acrylics, and probably a bit better than carrageenan alone, as as I find that acrylics degrade a pure carrageenan size more quickly than traditional European marbling paints made with pigments, water, and a gum binder. Last I knew, the cold water dispersible "J" grade was sold by Earth Guild in Asheville <www.earthguild.com/>, but you might check with them to see if that's still the case. It's a far higher quality product than the product sold by Daniel Smith, which is produced by Van Waters & Rogers. Just remember that what is sold as "Methyl Cellulose" is not the same! I posted about this in the past (search the archives), but there is also a lot of new, freely available information posted on Dow's website.
--- In Marbling@yahoogroups.com, "Joan" <rfnewman1@...> wrote:
> Is Sodium Alginate the same thing as Carrageenan? Dharma Trading sells both.The Sodium alginate (sea weed) is so much cheaper.