Rimmel London Lasting Matte Concealer Versus Laura Mercier Flawless Fusion Ultra Longwear Concealer

This ingredient is a silicone-based emulsifer that helps the water and oil phases play nicely together. It's so effective because one end of the molecule loves oil and the other one loves water.

Besides holding formulas together, it also leaves a silky and lightweight feel on skin without the greasiness. A manufacturer also claims it can help with the controlled release of active ingredients.

Ci 77891 is a white pigment from Titanium dioxide. It is naturally found in minerals such as rutile and ilmenite.

It's main function is to add a white color to cosmetics. It can also be mixed with other colors to create different shades.

Cyclopentasiloxane, or D5, is a silicone used to improve texture of products and trap moisture.

D5 is considered lightweight and volatile. Volatile means it evaporates quickly after application. Once evaporated, D5 leaves a thin barrier that helps keep skin hydrated.

This ingredient is a silicone elastomer that works as a texture enhancer, adds a silky slip, and also helps absorb excess oil.

Because it's a large macromolecule that's insoluble in water and chemically inert, it's not expected to penetrate or be absorbed into skin.

Laureth-7 is created by the ethoxylation of lauryl alcohol using ethylene oxide. Lauryl alcohol is a fatty alcohol with hydrating properties.

This ingredient is an emulsifier and cleansing ingredient. As an emulsifier, it is used to prevent ingredients from separating. It also helps cleanse the skin by gathering dirt, oil, and pollutants to be rinsed away.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

Magnesium Sulfate is a salt. More specifically, it is an epsom salt, or the bath salt used to help relieve muscle aches.

Despite having ‘sulfate’ in the name, it isn’t a surfactant or cleansing agent like sodium lauryl sulfate. Unlike those sulfates, magnesium sulfate doesn’t have the same cleansing or foaming properties (it's simply a type of salt).

Pentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.

The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.

This ingredient is a solvent. It helps dissolve active ingredients and alter the texture of products.

Propylene Carbonate is commonly used in makeup and with clay, such as montmorillonite or bentonite.

Tribehenin comes from glycerin and behenic acid.

It is used as an emollient, or moisturizer. Emollients form a thin barrier on skin to prevent moisture from escaping.

Triethoxycaprylylsilane is a silicon-based surface modifier that makes sunscreens feel silky and makeup stay put.

Its main job is to coat mineral particles like titanium dioxide, zinc oxide, and color pigments in a thin, oily layer so they spread smoothly, don't clump, and stick to skin better.

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.