Clinique Broad Spectrum SPF 50 Mineral Sunscreen Fluid for Face Versus Supergoop! Mineral Mattescreen SPF 40 PA+++ - US

Polyhydroxystearic Acid is a soft wax made from castor oil.

It is is a texture thickener, emulsifier, and film-former. Emulsifiers prevent ingredients from separating, such as oils and waters.

Silica is a mineral naturally found in our skin. It helps to thicken and smooth the texture of a product. It also acts as an agent for other ingredients by increasing the absorption of other ingredients into the skin.

Silica is often used for absorption and can help reduce shine when products are applied. Silica occurs in naturally in materials like clay and sandstone, and it can also be produced synthetically.

Titanium Dioxide is a mineral (or physical) sunscreen ingredient that provides broad-spectrum protection by blocking both UV-A and UV-B rays.

It sits on the skin’s surface and primarily reflects and scatters UV light and also absorbs some of it.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

Zinc Oxide is a mineral broad-spectrum UV filter; it is the broadest UVA and UVB reflector approved by the FDA. While it is most commonly man-made for cosmetics, it can naturally occur in zincite, a rare mineral.

Today, traditional and nano-sized zinc oxide can be found in beauty products. Nano-sized zinc oxide can enhance a product's UV protection. While it is not believed to have a negative effect on skin, nano-zinc oxide may be harmful to coral reefs - though the verdict is not entirely out on this one.