• Chemistry: Al2Si2O5(OH)4, Aluminum Silicate Hydroxide • Class: Silicates • Subclass: phyllosilicates. • Groups: The Clays and the Kaolin Group. • Uses: In the production of ceramics, as a filler for paint, rubber and plastics and the largest use is in the paper industry to produce a glossy paper such as is used in most magazines. • Specimens Kaolin, which is named for its type locality, Kao-Ling, is a common phyllosilicate mineral. It lends it name to the Kaolin Group, members of which also belong to the larger general group known as the Clays. Kaolin's structure is composed of silicate sheets (Si2O5) bonded to aluminum oxide/hydroxide layers (Al2(OH)4) called gibbsite layers. ibbsite is an aluminum oxide mineral that has the same structure as these aluminum layers in Kaolin. The silicate and gibbsite layers are tightly bonded together with only weak bonding existing between these silicate/gibbsite paired layers (called s-g layers). The weak bonds between these s-g layers cause the cleavage and softness of this mineral. The structure is very similar to the Serpentine Group and at times the two groups are combined into a Kaolin-serpentine Group. Kaolin shares the same chemistry as the minerals halloysite, dickite and nacrite. The four minerals are polymorphs; meaning they have the same chemistry, but different structures. All four minerals form from the alteration (mostly weathering) of aluminum rich silicate minerals such as feldspars. Kaolin is by far the most common and most clay deposits contain at least some Kaolin. In fact, clay deposits will frequently be nearly 100% Kaolin pure! Kaolin is important to the production of ceramics and porcelain. It is also used as filler for paint, rubber and plastics since it is relatively inert and is long lasting. But the greatest demand for Kaolin is in the paper industry to produce a glossy paper such as is used in most magazines.

Kaolin - KSP1 Physical 100 <32 Particle Size Distribution [¥ì m] 100 <20 50 <2 10.5 At 105 ¢ªC Modulus of Rapture (kg/cm2) 18.8 At 900 ¢ªC 2.9 At 105 ¢ªC Shrinkage (%) 6.7 At 1250 ¢ªC 11.9 At 1400 ¢ªC 16.5 At 1250 ¢ªC Water Absorption (%) 10.9 At 1400 ¢ªC 93 Green Brightness (%) 97 At 1250 ¢ªC 98 At 1400 ¢ªC 2.31 Density Power (g/Cm3) 46 Plasticity ( Peff) H= 16 12500 Viscosity [CP] Sp: 3 R.P.M:5 Solid = 40% Water = 60% 7.3 Ph 48.10 SiO2 Chemical Analysis (%) 36.85 Al2O3 0.05 Fe2O3 0.52 TiO2 0.28 CaO - MgO 0.15 Na2O 0.36 K2O 13.69 L.O.I >91 Kaolin Mineralogical Composition (%) <2 Montmorilonit <3 Lllite - Calcite <5 Quartz - Feldspare

“Kaolin in Cosmetics” Kaolin (also known as China clay, hectorite or magnesium silicate) is natural soft clay. In cosmetics, kaolin helps to cleanse and exfoliate dead skin cells and debris from the surface. It adds absorbency, texture and bulk to cleansers. Kaolin is an active ingredient usually found in thick skincare products such as mask. It’s a natural, white mineral that goes beyond pottery. Because it’s of a safe nature and has great absorbency and soothing properties, it’s quite the popular ingredient in formulas designed to purify. It does a great job for combination and sensitive skin types and will seriously help in clearing pores and soaking up excess moisture without causing flakiness or overly dry patches. So many foundations and powders can prompt the skin to produce more oil but kaolin products cause to prevent this issue and keep skin looking fresh and matt.

SiO2 68.050 Al2O3 22.298 TiO2 0.290 Fe2O3 0.160 CaO 0.140 MgO 0.275 K2O 0.173 Na2O 0.206 LOI 8.150

Hardness 1.5 - 2 (can leave marks on paper) Specific gravity 2.6 (average) Cleavage Perfect in one direction, basal Color Usually white, colorless, greenish or yellow Fracture Earthy Luster Earthy Streak White Transparency Crystals are translucent Crystal System Triclinic; 1 Crystal Habits Foliated and earthy masses. Crystals of any size are quite rare, usually microscopic. Other Characteristics Clay like properties when water is added. Best Field Indicators Habit, softness, color, luster and clay like properties

* Kaolin (a clay mineral) and mica can be substituted for talc in the production of rubber, paint, and plastics. * Kaolin can be used in place of talc in paper production. * Kaolin (a clay mineral) and mica can be substituted for talc in the production of rubber, paint, and plastics.

“What Historical background is known for Kaolin?” The mineral Kaolin has an ancient use as a skincare product. Like other clays, kaolin is very absorbent, and it can pull oils and dirt out of the skin. It is commonly used in clay masks or as an additive to baths to sooth the skin, and it is also included in numerous cosmetics. Powdered forms may be dusted on the face to absorb oil and reduce greasiness, while mineralized creams can be used to soothe dry skin or to reduce oiliness, depending on how they are formulated. Companies which carry natural skin care products often stock pure kaolin which people can use to make their own cosmetics and skin care products. Another historic use of this mineral Kaolin is as a remedy for gastrointestinal upset. People once ate kaolin because the clay coated the stomach to soothe irritation, and it absorbed bacteria and viruses which caused disease, as well as absorbing loose water, which caused the stools to firm. Some cultures continue to eat clays for stomach pain, and the mineral has also been integrated into many stomach care products, such as the liquid suspensions people take to treat diarrhea.

Kaolin is an industrial mineral used primarily as an inert filler and customers combine it with other raw materials in a wide variety of applications. Kaolin is part of our natural world. Its uses are multiple and diversified. Kaolin’s whiteness and plasticity make it extremely suitable for its extensive use as a filler, extender, ceramic raw material and pigment. It is also an important raw material to refractories, and to catalyst, cement and fiber glass industries. Kaolin is used in many applications. It is a unique industrial mineral, which remains chemically inert over a relatively wide pH range and it offers excellent covering when used as a pigment or extender in coated films and filling applications. In addition, it is soft and non-abrasive and has a low conductivity of heat and electricity. The two largest applications of kaolin are the coating of paper to hide the pulp strands and the production of high grade ceramic products.