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MAC Prep + Prime Highlighter

MAC
Prep + Prime Highlighter

A pen-style highlighter that efficiently brings a soft, sheer wash of colour to the skin. With its precision application, it adds radiance just where you want it.
Uploaded by: muncho99 on

MAC Prep + Prime Highlighter
Ingredients explained

Also-called: Aqua;Water | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying. 

One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time. 

What-it-does: emollient, solvent

A super commonly used 5 unit long, cyclic structured silicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel

It's often combined with the non-volatile (i.e. stays on the skin) dimethicone as the two together form a water-resistant, breathable protective barrier on the skin without a negative tacky feel.

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant, solvent, viscosity controlling | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive. 

Also-called: Salt | What-it-does: viscosity controlling

Sodium chloride is the fancy name of salt. Normal, everyday table salt

If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. The reason for this is that salt acts as a fantastic thickener in cleansing formulas created with ionic cleansing agents (aka surfactants) such as Sodium Laureth Sulfate. A couple of percents (typically 1-3%) turns a runny surfactant solution into a nice gel texture.

If you are into chemistry (if not, we understand, just skip this paragraph), the reason is that electrolytes (you know, the Na+ and Cl- ions) screen the electrostatic repulsion between the head groups of ionic surfactants and thus support the formation of long shaped micelles (instead of spherical ones) that entangle like spaghetti, and viola, a gel is formed. However, too much of it causes the phenomenon called "salting out", and the surfactant solution goes runny again. 

Other than that, salt also works as an emulsion stabilizer in water-in-oil emulsions, that is when water droplets are dispersed in the outer oil (or silicone) phase. And last but not least, when salt is right at the first spot of the ingredient list (and is not dissolved), the product is usually a body scrub where salt is the physical exfoliating agent

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1

Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.

As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity. 

As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types). 

What-it-does: emulsifying

A silicone emulsifier that helps water and silicone oils to mix nicely together. It can also be used together with plant oil + silicone oil mixtures. 

A light and silky, silicone-based emulsifier that helps water and silicone oils to mix nicely together. It is water-soluble and it can impart lubricity and a pleasant skin feel.

What-it-does: solvent, emulsifying, perfuming, surfactant/cleansing | Irritancy: 0-1 | Comedogenicity: 0-2

Similar to other glycols, it's a helper ingredient used as a solvent, or to thin out thick formulas and make them more nicely spreadable. 

Hexylene Glycol is also part a preservative blend named Lexgard® HPO, where it helps the effectiveness of current IT-preservative, phenoxyethanol

Diglycerin - goodie

The big brother of glycerin. It's also a natural moisturizing factor that reduces water evaporation from the upper layer of the skin and helps to keep water in the skin so that it stays nicely hydrated.

Compared to glycerin, it has a larger molecular structure (kind of a double glycerin). Thanks to this, it penetrates slower into the skin but gives longer lasting moisture and less sticky, better skin-feel.

What-it-does: emulsifying

We don't have description for this ingredient yet.

Also-called: Cetyl Dimethicone Copolyol | What-it-does: emulsifying, surfactant/cleansing

A silicone emulsifier that helps water and silicone oils to mix nicely together. 

What-it-does: viscosity controlling

An  odorless, slightly yellowish powder that's used as a polymer microsphere (a tiny little ball from repeated subunits). It gives products an elegant, silky texture and better slip. It can also scatter light to blur fine lines while letting enough light through so that the skin still looks natural.

What-it-does: emollient

A fast spreading emollient ester (hexyl alcohol + lauric acid) that's used in water in oil emulsions or in water-free formulas. It gives a light skin feel. 

Also-called: Aluminum Oxide, Al2O3 | What-it-does: viscosity controlling, absorbent/mattifier, abrasive/scrub

A multi-functional helper ingredient that's used mainly as a pigment carrier.  The pigment can be an inorganic sunscreen (such as titanium dioxide) or a colorant that is blended with alumina platelets and then often coated with some kind of silicone (such as triethoxycaprylylsilane). This special treatment enables pigments to be evenly dispersed in the formula and to be spread out easily and evenly upon application. It is super useful both for mineral sunscreens as well as for makeup products. 

Other than that, alumina can also be used as an absorbent (sometimes combined with the mattifying powder called polymethylsilsesquioxane), a viscosity controlling or an opacifying (reduces the transparency of the formula) agent.

A clear, light yellow liquid that is used to coat pigments (such as inorganic sunscreen agents or colorants) in cosmetic products.  The coating helps to stabilize pigments in the formulas and also helps them to spread easily and evenly on the skin. 

A type of silicone elastomer (rubber-like material with both viscosity and elasticity) whose major function is forming a nice film on the skin.

It is also cosmetically very elegant with a non-tacky, non-oily and smooth skin feel. It also works as a stable delivery system of active materials, has sebum absorption and control properties and upon application, it transforms into a matte appearance with a powdery after feel.

A white powdery thing that's the major component of glass and sand. In cosmetics, it’s often in products that are supposed to keep your skin matte as it has great oil-absorbing abilities. It’s also used as a helper ingredient to thicken up products or suspend insoluble particles. 

A not-very-interesting helper ingredient that is used as an emulsifier and/or surfactant. Comes from a coconut oil derived fatty alcohol, lauryl alcohol.

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

It is typically used in tiny amounts, around 0.1% or less.

What-it-does: preservative

It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.

It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic. 

Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10). 

It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.

What-it-does: preservative

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4). 

But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.

BTW, it’s also a food preservative and even has an E number, E202.

Also-called: CI 77019 | What-it-does: colorant

A super versatile and common mineral powder that comes in different particle sizes. It is a multi-tasker used to improve skin feel, increase product slip, give the product light-reflecting properties, enhance skin adhesion or serve as an anti-caking agent.

It is also the most commonly used "base" material for layered composite pigments such as pearl-effect pigments. In this case, mica is coated with one or more metal oxides (most commonly titanium dioxide) to achieve pearl effect via the physical phenomenon known as interference. 

Also-called: Ci 77491/77492/77499 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

A bit of a sloppy ingredient name as it covers not one but three pigments: red, yellow and black iron oxide.

The trio is invaluable for "skin-colored" makeup products  (think your foundation and pressed powder) as blending these three shades carefully can produce almost any shade of natural-looking flesh tones. 

Also-called: Titanium Dioxide/Ci 77891;Ci 77891 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

Ci 77891 is the color code of titanium dioxide. It's a white pigment with great color consistency and dispersibility.

Also-called: Ci 77163 | What-it-does: colorant

Bismuth Oxychloride has been around since the 1950s and it was one of the first synthetic materials to give a pearl-like effect in cosmetic products. It is a white powder with a fabulous sheen and a nice skin feel and it is still very popular in decorative cosmetics. 

It has one major drawback: it is sensitive to light. Upon prolonged UV exposure, it can lose its sheen and become gray.

Also-called: Blue 1;Ci 42090 | What-it-does: colorant

CI 42090 or Blue 1 is a super common synthetic colorant in beauty & food. Used alone, it adds a brilliant smurf-like blue color, combined with Tartrazine, it gives the fifty shades of green.

Also-called: Ci 75470 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

Carmine is a natural pigment that gives a bright, strawberry red shade. It counts as a special snowflake as it is the only organic pink/red colorant permitted for use around the eye area in the US.

Outside of the US though, it is not that often used, as unlike most other colorants (that tend to be synthetic or if natural, plant-derived), Carmine is animal-derived and comes from an insect called Coccus cacti. This makes it both very expensive and excludes it from animal-friendly, vegan cosmetic products.  

Also-called: Chromium Oxide Green;Ci 77289 | What-it-does: colorant

An inorganic (as in no carbon in its molecule, it is Cr2O3X(OH), the hydrated version of this guy) pigment that gives blue-green shades. It is not permitted in lip products in the US. 

Also-called: Ci 77288 | What-it-does: colorant

An inorganic (as in no carbon in its molecule, it is Cr2O3) pigment that gives dull olive green shades. It is not permitted in lip products in the US. 

Also-called: Ferric Ferrocyanide, Ferric Ammonium Ferrocyanide, Iron Blue;Ci 77510 | What-it-does: colorant

An inorganic (as in no carbon in its molecule) pigment that has a very intense, dark blue color. It is not permitted in lip products in the US, and only the version Ferric Ammonium Ferrocyanide is permitted in the EU. 

Also-called: Ci 77007 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

An inorganic (as in no carbon in its molecule) pigment that can range in shade from blue (most common) to violet, pink or even green. It is not permitted in lip products in the US.

Also-called: Tartrazine, Yellow 5;Ci 19140 | What-it-does: colorant

Ci 19140  or Tartrazine is a super common colorant in skincare, makeup, medicine & food. It’s a synthetic lemon yellow that's used alone or mixed with other colors for special shades. 

FDA says it's possible, but rare, to have an allergic-type reaction to a color additive. As an example, it mentions that Ci 19140 may cause itching and hives in some people but the colorant is always labeled so that you can avoid it if you are sensitive. 

You may also want to take a look at...

what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does emollient | solvent
It's a super commonly used water-thin volatile silicone that gives skin and hair a silky, smooth feel.  [more]
what‑it‑does moisturizer/humectant | solvent | viscosity controlling
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does viscosity controlling
Sodium chloride is the fancy name of salt. Normal, everyday table salt.  If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. [more]
what‑it‑does emollient
irritancy, com. 0, 1
A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does emulsifying
A silicone emulsifier that helps water and silicone oils to mix nicely together. [more]
what‑it‑does emollient | emulsifying | surfactant/cleansing
A light and silky, silicone-based emulsifier that helps water and silicone oils to mix nicely together. [more]
what‑it‑does solvent | emulsifying | perfuming | surfactant/cleansing
irritancy, com. 0-1, 0-2
Similar to other glycols, it's a helper ingredient used as a solvent, or to thin out thick formulas and make them more nicely spreadable.  Hexylene Glycol is also part a preservative blend named Lexgard® [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
The big brother of glycerin. A natural moisturizing factor that compared to glycerin penetrates slower into the skin but gives longer lasting moisture and less sticky, better skin-feel. [more]
what‑it‑does emulsifying
what‑it‑does emulsifying | surfactant/cleansing
A silicone emulsifier that helps water and silicone oils to mix nicely together. 
what‑it‑does viscosity controlling
A polymer microsphere that gives products an elegant, silky texture. Can also scatter light to blur fine lines. [more]
what‑it‑does emollient
A fast spreading emollient ester (hexyl alcohol + lauric acid) that's used in water in oil emulsions or in water-free formulas. It gives a light skin feel. 
what‑it‑does viscosity controlling | abrasive/scrub
A multi-functional helper ingredient that's used mainly as a pigment carrier helping pigments in mineral sunscreens and color cosmetics to flow freely and evenly and not to clump. [more]
A clear, light yellow liquid that is used to coat pigments (such as inorganic sunscreen agents or colorants) in cosmetic products.  [more]
A type of silicone elastomer (rubber-like material with both viscosity and elasticity) whose major function is forming a nice film on the skin. [more]
what‑it‑does viscosity controlling
A white powdery thing that can mattify the skin and thicken up cosmetic products. [more]
what‑it‑does emulsifying | surfactant/cleansing
A not-very-interesting helper ingredient that is used as an emulsifier and/or surfactant. Comes from a coconut oil derived fatty alcohol, lauryl alcohol. [more]
what‑it‑does chelating | viscosity controlling
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does preservative
A not so strong preservative that doesn’t really work against bacteria, but more against mold and yeast. [more]
what‑it‑does colorant
A mineral powder used to improve skin feel, increase product slip, give the product some light-reflecting properties, enhance skin adhesion or serve as an anti-caking agent. A real multi-tasker. [more]
what‑it‑does colorant
irritancy, com. 0, 0
A mix of red, yellow and black iron oxide. [more]
what‑it‑does colorant
irritancy, com. 0, 0
Titanium dioxide as a colorant. It's a white pigment with great color consistency and dispersibility.
what‑it‑does colorant
Bismuth Oxychloride has been around since the 1950s and it was one of the first synthetic materials to give a pearl-like effect in cosmetic products. It is a white powder with a fabulous sheen and a nice skin feel and it is still very popular in decorative cosmetics.  It has one major drawback: [more]
what‑it‑does colorant
Synthetic colorant with smurf-like blue color. [more]
what‑it‑does colorant
irritancy, com. 0, 0
Carmine is a natural pigment that gives a bright, strawberry red shade. It counts as a special snowflake as it is the only organic pink/red colorant permitted for use around the eye area in the US. Outside of the US though, it is not that often used, as unlike most other colorants (that tend to be synthetic or if natural, plant-derived), Carmine  [more]
what‑it‑does colorant
An inorganic (as in no carbon in its molecule, it is Cr2O3X(OH), the hydrated version of this guy) pigment that gives blue-green shades. It is not permitted in lip products in the US.  [more]
what‑it‑does colorant
An inorganic (as in no carbon in its molecule, it is Cr2O3) pigment that gives dull olive green shades. It is not permitted in lip products in the US.  [more]
what‑it‑does colorant
An inorganic (as in no carbon in its molecule) pigment that has a very intense, dark blue color. It is not permitted in lip products in the US, and only the version Ferric Ammonium Ferrocyanide is permitted in the EU.  [more]
what‑it‑does colorant
irritancy, com. 0, 0
An inorganic (as in no carbon in its molecule) pigment that can range in shade from blue (most common) to violet, pink or even green. It is not permitted in lip products in the US. [more]
what‑it‑does colorant
A super common colorant with the color yellow. [more]