1 kg. 
Clay masks benefit the skin by drawing out impurities, absorbing excess oil, and deep-cleaning pores to help prevent breakouts and minimize their appearance. They also exfoliate dead skin cells, leaving the skin feeling smoother and looking more refreshed and matte. Additionally, they can refine the look of pores, provide a source of beneficial minerals, and soothe the skin, while some types have anti-bacterial properties. 
Deep cleaning and purification 
Draws out impurities: Clay acts like a magnet, pulling dirt, oil, and toxins from deep within the pores.
Cleanses pores: By removing built-up impurities, clay masks help to unclog pores and can minimize the appearance of blemishes, including those from "maskne". 
Oil control
Absorbs excess oil: Clay absorbs excess sebum from the skin's surface, which reduces shine and gives oily skin a more matte appearance.
Regulates sebum: Ingredients like zinc in some masks can help regulate oil production. 
Skin refinement and smoothing 
Exfoliates: Clay masks help to slough away dead skin cells, resulting in a fresher and smoother complexion.
Minimizes pores: They can tighten pores, making them look smaller.
Softens and revitalizes: Some clays are rich in minerals like silica, iron, and calcium, which can soften the skin and promote a healthy glow. 
Other benefits
Mineral-rich: Many clays are packed with beneficial minerals like silica, magnesium, and zinc that nourish the skin.
Soothes: Certain clay masks can soothe the skin and may help with conditions like eczema or dermatitis, thanks to their binding and detoxifying properties.
Supports a healthy scalp: When used on the scalp, clay masks can absorb excess oil and impurities, which helps to improve scalp health and can make hair appear fuller.