Tartaric acid is pH balancer and your friend in getting cochineal to release brilliant reds. It helps shift an alkaline dye bath into acidic.
Content: Tartaric Acid
Storage: Store in dry, cool place away from light.
For your study of natural colors:
NATURAL SOAP COLOR by Jo Haslauer is the perfect companion for your study of soap making with natural color. WILD COLOR by Jenny Dean is a marvelous book to kick start one's study of natural dye techniques and color palettes. BRILLIANT COLOURS by Cheryl Kolander, doyen of natural dyeing, is another book of interest if one is interested in developing a very personal connection with natural colors.
Sold in convenient measurement units. Choose a measurement unit to suit your project requirement. Sample comes in handmade glass vial with metal cap (2 x 0.75 inches). Included dye will weigh approx 0.15 oz / 5g.