Borax is a naturally occurring mineral salt that is often used as a home cleaner, a stain remover on surfaces and clothes, a fabric and water softener, and a soap booster. You’ll find it with the laundry products at the grocery.
Castile soap is a type of soap made from vegetable oil rather than animal fat or synthetic substances. You can find it in drugstores.
Cream of tartar (potassium bitartrate) is a by-product of winemaking that is used in food and as a cleansing agent. Small amounts may be purchased at a grocery; buy in bulk from a wine-making supplier.
Linseed oil (cold pressed from the seeds of flax, sometimes called flaxseed oil). Used as a wood treatment, it protects the surface. Available from paint stores.
Turpentine is distilled from pine resin, which is obtained by tapping trees of the genus Pinus. It is used as a solvent. Available from paint stores.
Washing soda (sodium carbonate, also known as soda ash) is a highly alkaline chemical compound which can be used to remove stubborn stains from laundry and for other cleaning purposes. Don’t confuse washing soda with washing powder (powdered detergent) or with baking soda. Arm & Hammer washing soda is usually stocked with the bleach in the laundry aisle. If you don’t find it in the national chains, try a local chain store, or ask a local grocer to order it for you.