Well, the short answers are; the kind best suited for your needs, yes, yes and no. LOL. Okay, I am writing this at four am, and I am a bit punchy, so while I thought that was funny, I am sure it really isn't. Please forgive me, and read on for a more detailed explanation.
While there are many colors of clay, many countries that harvest clay, and many different names of clay, there are basically just a few types of clay, and some of these types of clay have several different subsets that belong in that group, kind of like a "genus" in relation to a "'species". So let's look at the broad types of clay available. There is Bentonite, Multani Mitti,
Montmorillonite, Illite, and Kaolinite clay.
Kaolin clay comes in several colors, all of which are Kaolinite clay. They are generally called by their color; yellow, pink, red, rose, and white.
Kaolin clay consists of kaolinite, and is the mildest of all clay.
The White, Yellow, and Pink Kaolin clay are suitable for all skin types, even for sensitive skin. They help to stimulate circulation to the skin, while gently exfoliating and cleansing it. Unlike most other clay, these Kaolin do not draw the skin's oils, which is why they can be used on all skin types, even on dry skin. These types are perfect in sensitive skin formulations.
The White kaolin clay is also sometimes called China clay, China white clay, or simply, White Clay. The Pink can be used in body powders to keep the skin dry.
The Rose clay is tinted with iron oxides and gives a beautiful pink color to soaps and powders.
The Red kaolin, however, is mildly absorbent, and is used for drawing oils and toxins from the skin. It is suitable for inclusion in facials and body wraps for those with normal skin. It too can be used as a natural colorant in soap making.
French Green clay, often used in high end spa products and cosmetics, is primarily consists of Montmorillonite clay. This clay is highly efficient at drawing oils and toxins from the skin.Similar to many other clays, montmorillonite swells with the addition of water. However, some montmorillonites expand considerably more than other clay, due to water penetrating the interlayer molecular spaces and concomitant adsorption. The amount of expansion is due largely to the type of exchangeable cation contained in the sample. French Green Clay is rich in important minerals and phyto-nutrients, and is the most commonly used therapeutic clay, most often for facials and body wraps. It can also be used in soaps and body/foot powders. But you should limit face applications to once a week on normal skin, and up to two times a week on oily skin complexions. This clay should not be used for those with sensitive or dry skin types.
Illite clay is very similar in structure to Montmorillonite, and it does not expand with the addition of water. Green Illite clay is used for the detoxification and exfoliation of the skin. It is efficient at drawing oils and toxins from the skin, and is frequently mistaken for French Green Clay. Of course it can be used in soaps and body/foot powders, but like the French green, it should only be used once a week on normal skin, and up to two times a week on oily skin complexions. This clay should not be used on sensitive or dry skin types either.
The Yellow and the Red Illite clay are also efficient at drawing oils and toxins from the skin, are suitable for oily skin, have structure similar to Montmorillonite, and do not expand with water either. They too are used for detoxifying and exfoliating the skin, and their pretty coloring makes them great natural color additives for soaps, balms, powders and thick emulsions.
Another red clay is Rhassoul, a Moroccan lava clay, it is a Kaolinite clay.
Rhassoul is a super fine, ancient clay, found deep below the Atlas Mountains in Morocco. Although it is difficult to obtain from the deep clay beds, it has been used for centuries. It is rich in minerals such as silica, magnesium, iron, calcium, potassium and sodium. This clay is a strong cleansing clay. It will draw excess oils from the skin, stimulate the circulation, and act as a powerful astringent for oily skin and hair. It is used in many spas around the world, mainly for facials and body wraps. This pretty red clay also makes a nice, natural colorant for soaps and powders. Like the other strong cleansers, this should not be used on sensitive or dry skin, and applications should be limited to either once or twice a week on very oily skin. Those with normal skin may be able to utilize this clay once a week, but I usually suggest either a blend with a milder clay, or only using once a month.
Bentonite Clay is a highly absorbent clay. It is actually a combination of montmorillonite and volcanic ash, and is considered one of the best choices for making a (clay) poultice. Like other clay, it pulls oils and toxins from the skin, and is best suited for oily skin types. Bentonite clay is great for making a shaving soap, and for use in oily scalp and hair treatments.
Multani Mitti clay is better known as Fullers Earth clay, but is also sometimes called, Indian Fullers Earth. It is formed by the decomposition of volcanic ash, and is very similar in its nature to kaolin clay. Back in the day, Fullers used this clay to clean sheep's wool, prior to its being spun. That is how it came to be named Fuller's Earth. This clay is highly absorbent, and is good for drawing excess oils from the skin, while stimulating circulation to the skin. It is suitable for oily skin and hair treatments, but should not be used on sensitive or dry skin at all. Large area treatments should be limited to no more than once weekly, although spot treatments are usually well tolerated two to three times weekly. This clay is often used in making a "mechanics soap", as it works well combatting grease and dirt, and is a great hand cleaner.
Sea clay is a kaolinite as well. It is a grayish green color, and has high concentrations of minerals present. While the clay draws the skin's oils, it also remineralizes the skin. It is suitable for all skin types.
Dead Sea Mud is also a kaolinite, one that is rich in the minerals found (only) at the bottom of the Dead Sea. Whether used alone, or in combination with other cosmetic grade clays, Dead Sea clay is suitable for facial, body wrap, hair wrap and soap formulations. It is suitable for all skin and hair types. I have done a couple of posts on Dead Sea Mud and Salts that go into great depth. So, if you missed them, please take a look!
Just a few notes/tips:
-When making a face mask with clay, use purified/distilled water to moisten your clay, you will only need a small amount.
-Always pour the clay out into another container [or your palm] before adding the water. Never mix the water into the clay container. Never put wet utensils or your fingers into the clay container. As long as the powder stays moisture free, it will last indefinitely. Moisture means the introduction of bacteria and contamination.
-When you add the liquid to the clay, do so slowly. You don't need a lot, only mix until you have a nice, paste consistency. If you desire, this is when you should add skin safe essential oil(s).
-The thicker the clay paste is when applied to the skin, the more drawing power it will have. So, when you need to boost the "power", alter the paste thickness, so not extend the time you leave the mask on.
-You can substitute infusions, hydrosols, yogurt, juice, cream or milk for the distilled water if you'd like. Each has properties that may be beneficial to your skin, so research and experiment until you find the perfect blend for you!
-Always error on the side of caution. Begin with a thin or moderate paste, at the lower time frame, with the mildest clay and liquid that you have. See what it does to your skin, then make alterations based upon those results.
-When making cp soap and adding clay, generally you add 1 tablespoon per pound of oils (when using mild clay) and 1 teaspoon per pound of oil when using the stronger clay. Since clay likes to clump when it's added to the soap pot, try removing about a 1/2 cup of batter adn mixing all of your clay into that. Use a frother to mix well, then add the half cup back into the whole pot and mix well.