Science of Facial Masks and Facial Clay

Both mud and clay masks have many benefits to the skin when applied. Facial masks are often used in spa treatments and can also be purchased at stores for use at home. There are a wide variety of mud and clay masks available on the market, making the proper selection difficult. It is important to know what type of skin you have, and the characteristics of different facial clays, in order to select the one most appropriate for your skin.

Difference Between Mud vs Clay

Mud is a broad term that refers to a mixture of water and some combination of soil, which is made up of minerals, gases, and organic materials. Mud comes in many forms and types and is classified by the size of fine-grain soil present. Clays have the smallest particle size (less than .002 mm), while silt is slightly bigger (.002 mm to .05 mm), and sand is the largest (.05 mm to 2 mm).^[1]

Clay is made up of a variety of different materials and has a high aluminate and silicate content.^[2] Clays can also contain other materials such as iron oxide (rust) and rock fragments. These impurities can change the characteristics of the clay. For example, iron oxide colors clay red. The presence of silica increases plasticity, meaning it is easier to mold and form into shapes.^[3]

Kaolin Clay

Kaolin clay is derived from weathered rocks in hot, humid climates, and is one of the most versatile and widely used clays. It gently exfoliates and absorbs oils from the skin.^[4] Because it blends so well with water, it is used in many products, from masks to cleansers. Kaolin clays come in a variety of shades that work well on different skin types.

White kaolin clay for dry & sensitive skin

White kaolin clay is the mildest of clays and is less absorbent than other varieties, meaning it doesn’t draw as much oil from the skin. Because the clay is extremely moisturizing, it is often used for those with sensitive and dry skin.^[5] As opposed to absorption, white kaolin clay tends to soften the skin with gentle exfoliation. Other products such as cosmetic powders also contain white kaolin to help create a smooth, porcelain-like matte finish.

Yellow kaolin clay for dull & sensitive skin

Yellow kaolin clay is slightly more absorbent and exfoliating but still remains gentle enough for sensitive skin. It may also stimulate circulation, so you’ll probably find it in a lot of brightening masks.^[5]

Red kaolin clay for oily skin

Red kaolin clay has the most absorbing powers of the bunch and is best for oily skin. Therefore it is often added for skin care regimen of skin diseases with oily skin such as acne as well as detoxifying masks for the face or body.^[5]

Pink kaolin clay for sensitive & oily skin

Pink kaolin clay is pretty much a mixture of the white and red kaolin clays, making it potentially useful as part of a balanced skin care regimen for those with acne-prone skin that also tends to be more sensitive.^[5]

Bentonite Clay for Oily & Acne-Prone Skin

Bentonite clay is composed of weathered and aged volcanic ash sediments. It is highly absorbent, and therefore perfect for oily skin. Known for its detoxifying abilities, bentonite clay removes oil and dirt that has accumulated on the skin’s surface.^[6] Bentonite draws out oil and impurities, unclogs and shrinks pores, and can prevent acne with antibacterial properties.^[7] Its impurity-absorbing abilities make it ideal for oily, congested and acne-prone skin types, and is commonly used in over-the-counter acne treatments, bath soaks, foot, body, and face masks.

Because bentonite has incredible absorbing capabilities, it is usually recommended by skin care professionals for use only once a week. It can also be drying, so it is important to follow treatments up with your regular moisturizing routine.

French Green Clay for Oily & Acne-Prone Skin

French green clay comes from naturally occurring deposits in France. It has a soft texture and natural green color due to iron oxide and decomposed plant matter. Effective at drawing out impurities and containing highly absorbing properties, French green clay also works well for oily and acne-prone skin. This clay mask is ideal for detoxification, tightening pores, and evening the skin tone.

Studies have also shown that French green clay contains antimicrobial properties that have successfully contributed to healing bacterial skin infections.^[8]

Moroccan Rhassoul Clay for All Skin Types

Moroccan rhassoul clay is sourced from the Atlas Mountains in Morocco and contains high percentages of silica and magnesium. This facial clay absorbs excess oil, draws out toxins, and clears clogged pores.^[9] Rhassoul clay is a common choice to treat blackheads and exfoliate dead skin. Its skin calming and lightly hydrating properties are well suited to dry and sensitive skin types, and can even be used daily.

In addition to skin, rhassoul clay also provides therapeutic benefits to the hair. When applied as a hair mask, rhassoul clay restores volume and shine.^[9]

Fuller’s Earth Clay for Oily & Uneven Skin Tone

Fuller’s earth clay comes from ancient volcanic ash sediments and is a great oil absorber and exfoliant. Its lightening and brightening properties also make it a common choice for evening out the skin tone.^[10] This facial clay contains mild bleaching properties and is widely used as a skin-lightening agent. It is also great for reducing the appearance of dark spots and acne scars.^[11]

Because of its strong absorbing properties, Fuller’s Earth clay is typically suggested for weekly use. It is best for people with oily skin, as it can be drying for other skin types.