The term 'soapy powder mineral' is a reference to TALC, which is a soft, hydrous magnesium silicate mineral composed of magnesium, silicon, and oxygen. TALC is used in many industries, including papermaking, plastic, paint, and cosmetics. It is also used as a filler in pharmaceuticals and food products. TALC is known for its slippery feel and is often used in baby powder and other personal care products.