Michael: If you use makeup, have you ever wondered what you’re actually putting on your face? Well, think about it, and then be thankful that you weren’t alive 500 years ago. In the 1500s, toxic ingredients like lead were used to create perfectly smooth, white skin, and you can imagine how that went.

But thankfully, we’ve learned a lot more about chemistry since the 16th century! Makeup has been around for at least 10,000 years, and its ingredients have varied from poisonous chemicals to animal poop. But these days, most makeup is made in the lab.

And a lot of how makeup works, whether you’re trying to darken your eyelashes or smooth out your complexion, depends on its chemistry. So get ready to change the way you think about your morning routine, because here’s the chemistry behind common types of makeup.

Whether you use it yourself or not, lipstick is one of the most iconic cosmetics around. But only around 5% of its ingredients go into creating your favorite colors. Lipstick is mainly wax mixed with oils, with just a tiny bit of fragrances and dyes.

The wax gives the lipstick structure and also holds all the other ingredients together. Different lipsticks can use different types of wax, but most use beeswax or Carnauba wax, which comes from the Brazilian Carnauba palm tree. Carnauba wax is especially useful because it doesn’t melt until it reaches around 84 degrees Celsius, which means that even if you leave your lipstick in a hot car, you probably won’t end up with melted goop. There’s also usually castor oil, mineral oil, or even olive oil mixed in with the wax to help it spread.

Then there’s that last 5% — the fragrances and colors, many of which are created in the lab. But some colors can come from more natural sources. Cochineal bugs, for example, which live on cacti, produce carminic acid, which is used in some red dyes. Nothing like sprucing up your look with a little bug dye, right?

If solid lipstick isn’t your thing, you might still be a fan of lip stain or liquid lipstick. Lip stain is colored by the same ingredients as solid lipstick, but it stays on a lot longer and smudges less during the day.

With solid lipstick, the pigments are mixed with wax and oil, which can fade or rub off easily, like when you put your lips on a coffee cup. But with lip stain, the pigments are dissolved in water, gel, and alcohol. When you’re done putting it on, the alcohol evaporates, and the color dries right onto your lips.

This way, the color won’t come off as easily during the rest of your day. But while lip stains are longer-lasting, their alcohol content means they usually can’t contain the moisturizers lipstick can, so they’re also more likely to dry out your skin.

Eyeliner is another classic makeup staple. It’s great for sailing the seven seas aboard the black pearl — or if you just like a darker lash line. And, like with lip makeup, you have plenty of options, from sticks and pencils to liquids and creams. Either way, most eyeliners are made up of the same three ingredients.

First, you have film formers: complex chains of carbon, hydrogen, oxygen, and sometimes nitrogen, whose structure helps the eyeliner spread into a thin layer on your eyelid. Film formers help the eyeliner go on, but then it’s up to thickeners to keep the formula stable and help it stick to your eyes once it gets there. Like with lipstick, thickeners are usually a kind of wax or clay.

Finally, there are the pigments and dyes. With eyeliner, you’re likely to find chemicals like iron oxide, a compound made up of iron and oxygen that makes black and brown. But you can also find brighter compounds, like green chromium oxide, which is two chromium and three oxygen atoms, or bright blue ultramarine, which is made from aluminum, sodium, oxygen, and silicon. Your chemicals, your style.

The difference between the types of eyeliner mainly depends on the balance between the ingredients. With pencils or sticks, you’ll have more thickeners for a solid formula. Creams don’t have as many thickeners, so the mixture is thinner and can be spread with a brush. And liquid eyeliner works a lot like lip stain. The pigments are dissolved in water and alcohol, and the color dries onto your skin after it’s applied. So like lip stain, liquid eyeliner lasts the longest.

If you pick up a waterproof eyeliner, it’ll contain a silica derivative called dimethicone copolyol. Regular silica is two oxygen atoms bound to a silicon atom, but dimethicone copolyol is more complex and made from large groups of silicon, hydrogen, carbon, and oxygen.

The complicated structure makes it much better at repelling water than normal silica. This chemical is also common in shampoos and conditioners, where it keeps your hair nice and shiny.

If you want to add a bit more color to your look, you might try eyeshadow. In general, most eyeshadows start the same way. First, there’s a base — usually talc, a mineral made up of magnesium, silicon, and oxygen. Then, chemicals called binders are mixed in to make the powder sticks to your eyelids — which, you know, is usually helpful.

The most common binders are zinc or magnesium derivatives, which absorb oil and repel water to keep your eyeshadow in place. Sometimes, silica or nylon will be added to make sure the eyeshadow goes on smoothly, or zinc stearate, a kind of salt, will be added to make sure it doesn’t clump up if it’s exposed to water, like sweat or rain. Preservatives like glycol — chains of carbon, oxygen, and hydrogen — are also added to prevent bacteria from growing on the compact.

If you’re using a cream eyeshadow instead of a powder, there’s probably some castor oil or beeswax in there to make it creamy and spreadable. The color in cream eyeshadows dries right onto your skin, which can make this kind of eyeshadow last longer.

In ancient Greece, eyeshadow was colored by gems like malachite, which is green, or lapis lazuli, which is blue. But thankfully for your wallet, these days colors are generally made in the lab from less expensive ingredients. Some of the dyes are the same ones you’ll find in lipstick or eyeliner, but you might also find white titanium oxide or purple manganese violet in your color pallet.

No discussion about eye makeup would be complete without mascara. Whether you want to thicken, darken, or lengthen your lashes, there’s probably a mascara for you. You might have heard that mascara contains guano, or bat poop. But that’s just a myth! What some mascaras used to actually contain is guanine, a poop-free chemical used to make your eyelashes shimmer.

Today, a chemical called bismuth oxychloride — a combination of bismuth, oxygen, and chlorine — does the job instead. Beyond that, mascara is a mix of complex polymers, preservatives, and a thickening agent dissolved in a solvent like oil or water.

The polymers are made up of long chains that create a film to coat your eyelashes. And a thickening agent, like wax or oil, keeps it from being a runny, liquidy mess. Most mascaras are black, which means they’re colored with iron oxide like black eyeliner. But if you’re going for a bolder look, you’ll find the chromium oxide greens, ultramarine blues, and more to help you out.

Depending on which brand you buy, you might choose either a mascara made with no water or one made with a mixture of both oil and water. The kind with no water will likely be waterproof, but the water and oil mixture will be easier to take off at the end of the day.

In general, the lower a mascara’s water content, the more waterproof it will be. So if you’re preparing for a sad movie or an especially emotional day, just check the ingredients on your mascara label, and let science save you some trouble.

We’ve talked about a lot of makeup that’lll make parts of your face stand out more, but what about the kinds that help blend things? Well, that’s why there’s foundation and concealer.

Whether you want to even out your skin tone with foundation or just cover a zit with concealer, the point is to make your skin look as flawless as possible. There are a ton of these products, including solids, liquids, and even sprays, but they all start the same way.

Foundations and concealers usually have a base, moisturizers, colorants, and fillers. With solids, the base is oil and wax, while liquids and sprays have an oil and water base. The moisturizer depends on your specific brand, but fillers are used to make everything spread evenly and go on smoothly.

The most common filler is talc, the same mineral used in eyeshadow. Now, if your foundation looks streaky or cakey, it could be the way you’re applying it or because your skin is exceptionally oily or dry. But it could also be because the formula you are using is too thick, dries too quickly to blend in, or separates when it interacts with other products, like moisturizer or primer.

To create natural skin tones, the pigments you might find in foundation and concealer include iron oxides for darker browns and blacks, as well as titanium oxide, which comes in various shades of red, yellow, and black. On top of the basic ingredients, some foundations can even contain salicylic acid to fight acne, cornstarch to control oily skin, or other oils to keep dry skin moisturized.

Now that you’ve spent so much time getting your foundation and concealer ready, it helps to know it’s going to stay on all day. Which is where setting powder comes in. It’s kind of like eyeshadow for your entire face. The same iron oxides and titanium dioxides used in foundation are mixed into a base like talc powder.

Then, you can apply it to your skin with a brush or a powder puff, and it evens skin tone and helps foundation and concealer stay on longer. It works because it’s another layer between your makeup and your sweat or when you rub your face during the day. Since the base is great at absorbing small amounts of liquid, you can also apply setting powder throughout the day if you want to make your face less oily.

Now, have you ever noticed that a little too much setting powder sometimes looks thick and caked on? That has to do with the kind of powder you buy. You can either buy a solid, pressed powder in a compact, or you can buy a loose powder.

And even though the main ingredients are the same, there’s a key difference: Loose powder has smaller particles, which leads to a lighter finish. But to make a pressed powder, you have to add waxes and silica to make sure it stays solid, which also means you’ll have larger particles. This powder lumps together a lot more easily than the loose powder, which means it can clump up and create a caked on a look if you’re not careful.

So, it turns out there’s a lot more to makeup than meets the eye: with all the bases, moisturizers, fillers, solvents, and colors, you’re adding lots of different compounds to your bag when you browse through the cosmetics aisle. But at least now you know more about what you’re putting on your face, and what those compounds are for.

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