Guar gum is a natural non-ionic polysaccharide (galactomannan) that is isolated from the seeds of the guar tree Cyamopsis tetragonoba (pea tree), which is grown in India and Pakistan. 

Guar gum is used as a thickener and emulsion stabilizer. Increases frost resistance of water-based paints. Guar gum is a food additive E412 and, accordingly, can be used in children's and art watercolors, gouache and other paints.

Cheaper analogue of gum arabic.