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Rare Beauty by Selena Gomez Positive Light Under Eye Brightener

Positive Light Under Eye Brightener

A super lightweight liquid that instantly brightens, hydrates, and awakens undereyes with sheer to medium coverage for a fresh, radiant look in a flash.
Uploaded by: georgiat on

Rare Beauty by Selena Gomez Positive Light Under Eye Brightener
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. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

What-it-does: emollient

A silicone fluid that gives a nonoily, easy to spread emolliency to the formulas. It is also used as a water repellent additive and to reduce the tackiness and stickiness of other ingredients. It also imparts gloss, softness and better manageability to hair.

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

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

Also-called: Poly Vinyl Pyrollidone | What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 0

These three letters stand for Poly Vinyl Pyrollidone, a big molecule created from repeated units of Vinyl Pyrrolidone, aka VP. Its main thing is being an important film former. It was the first synthetic polymer introduced as a hair fixative in the 1950s instead of insect-derived Shellac. 

So PVP likes to attach itself to surfaces such as the hair and the skin and forms a nice, thin, even film there. The film is useful for holding a hairstyle or extending the wear of color cosmetics and sunscreens. The disadvantage of PVP is that the film is a bit brittle and that PVP loves water (hygroscopic) that tends to destroy the film. This is the reason why hair styled with a PVP based product loses its style in high humidity. To fix this problem, there are now several versions of VP containing film formers that are less sensitive to humidity, for example, the molecule called VP/VA Copolymer

The snappily named Lauryl Peg-9 Polydimethylsiloxyethyl Dimethicone is a silicone emulsifier fluid whose main thing is being a good dispersant for powders such as mineral UV filters or color pigments. 

According to the manufacturer Kobo, this partly water- and partly oily soluble form of dimethicone helps filters like Titanium Dioxide and Zinc Oxide disperse more evenly and thus provide better UV protection while also minimizing any white-cast that often comes hand-in-hand with mineral filters.

What-it-does: moisturizer/humectant, solvent | 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.

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.

What-it-does: emollient, emulsifying

The combination of glycerin + behenic acid that comes either in a fine powder or waxy solid form. Together with the di- and triglyceride of behenic acid, the trio has remarkable gelling properties helping cosmetic chemists to create ultra-soft and non-tacky waterfree gels. They also have great emulsion stabilizing properties, and work as high-performance compacting agents for makeup products that come in the form of pressed powders.

It's also vegetable origin, and Ecocert certified.

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. 

What-it-does: viscosity controlling

An organic derivative of hectorite clay, Disteardimonium Hectorite is used as a viscosity controller - it thickens up formulations to make them less runny.

It’s most popular use in cosmetics is in sunscreens, under the trademarked name Bentone 38 from Elementis. According to the manufacturer info, it is a real multi-tasker, including the ability to prevent pigments settling during storage, stabilizing a formula for longercreating a light and smooth skin feel and enhancing the water-resistance of sunscreen formulas
 

What-it-does: antioxidant

A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent

Also-called: Sunflower Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

What-it-does: emollient

Bearing a close relationship to the famous Dimethicone, Methicone is the slightly trimmed down version missing the methyl (-CH3)  groups on one side of the silicone chain. Like most silicones, it has nice emollient properties and improves the spreadability of products.

But Methicone's main thing in practice is not being an emollient but a silicone fluid for hydrophobization treatment of powders, i.e. making solid powders (mineral filters & color pigments) very water resistant and easily spreadable. Methicone does this by absorbing traces of water from the surface of pigments that is very useful for mineral sunscreens and makeup products. 

What-it-does: solvent

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives

It’s a handy multi-tasking ingredient that gives the skin a nice, soft feel. At the same time, it also boosts the effectiveness of other preservatives, such as the nowadays super commonly used phenoxyethanol

The blend of these two (caprylyl glycol + phenoxyethanol) is called Optiphen, which not only helps to keep your cosmetics free from nasty things for a long time but also gives a good feel to the finished product. It's a popular duo.

Also-called: Vitamin E Acetate | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 0

It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version. 

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E. 

What-it-does: viscosity controlling

A white, elastomeric silicone powder that gives a nice silky and powdery feel to the products. It also has some oil and sebum absorption capabilities. 

Also-called: EDDS | What-it-does: chelating

A helper ingredient that helps to neutralize the metal ions in the formula (they usually come from water) so it stays nice longer. The special property of this particular ingredient is that it's more effective against more problematic ions, like Cu (copper) and Fe (iron) compared to less problematic ones like Ca (calcium)  and Mg (magnesium).

We don't have description for this ingredient yet.

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

What-it-does: absorbent/mattifier, abrasive/scrub | Irritancy: 0 | Comedogenicity: 1

Talc is the major component of most powder makeup products (think face powder, eyeshadows, and blushers) that usually contain it up to 70%. Its two winning properties that make it very suitable for this role is its outstanding spreadability for a smooth application and its low covering power, aka translucency to avoid clown-like effects.

Chemically speaking, it is a clay mineral (hydrated magnesium silicate) that is mined in several countries. The drawback of mined minerals is potential impurities and the version used in cosmetics has to be white (not gray like cheaper grades), free from asbestos, sterilized and have thin plates for a maximum slip. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: astringent

We don't have description for this ingredient yet.

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: 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: 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.

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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 skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does emollient
A silicone fluid that gives a nonoily, easy to spread emolliency to the formulas. [more]
what‑it‑does emulsifying | surfactant/cleansing
A silicone emulsifier that helps water and silicone oils to mix nicely together. 
what‑it‑does viscosity controlling
irritancy, com. 0, 0
These three letters stand for Poly Vinyl Pyrollidone, a big molecule created from repeated units of Vinyl Pyrrolidone, aka VP. Its main thing is being an important film former. [more]
what‑it‑does emulsifying | surfactant/cleansing
The snappily named Lauryl Peg-9 Polydimethylsiloxyethyl Dimethicone is a silicone emulsifier fluid whose main thing is being a good dispersant for powders such as mineral UV filters or color pigments. According to the manufacturer Kobo, this partly water- and partly oily soluble form of dimethicone helps filters like Titanium Dioxide and Zinc Oxide disperse more evenly and thus provi [more]
what‑it‑does moisturizer/humectant | solvent
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 | emulsifying
The combination of glycerin + behenic acid that works as an oil-gelling, emulsion stabilizing or compacting (in pressed powders) agent. [more]
what‑it‑does viscosity controlling
A white powdery thing that can mattify the skin and thicken up cosmetic products. [more]
what‑it‑does viscosity controlling
An organic derivative of hectorite clay, Disteardimonium Hectorite is used as a viscosity controller - it thickens up formulations to make them less runny.It’s most popular use in cosmetics is in sunscreens, under the trademarked name Bentone 38 from Elementis. [more]
what‑it‑does antioxidant
A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent.
what‑it‑does emollient
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does emollient
Bearing a close relationship to the famous Dimethicone, Methicone is the slightly trimmed down version missing the methyl (-CH3)  groups on one side of the silicone chain. [more]
what‑it‑does solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does moisturizer/humectant | emollient
A handy multi-tasking ingredient that gives the skin a nice, soft feel and also boosts the effectiveness of other preservatives. [more]
what‑it‑does antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [more]
what‑it‑does viscosity controlling
A white, elastomeric silicone powder that gives a nice silky and powdery feel to the products. [more]
what‑it‑does chelating
A helper ingredient that helps to neutralize the metal ions in the formula (they usually come from water) so it stays nice longer. [more]
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does abrasive/scrub
irritancy, com. 0, 1
Talc is the major component of most powder makeup products (think face powder, eyeshadows, and blushers) that usually contain it up to 70%. Its two winning properties that make it very suitable for this role is its outstanding spreadability for a smooth application and its low covering power, aka translucency to avoid clown-like effects. [more]
what‑it‑does colorant
irritancy, com. 0, 0
A mix of red, yellow and black iron oxide. [more]
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
irritancy, com. 0, 0
Titanium dioxide as a colorant. It's a white pigment with great color consistency and dispersibility.