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Peter Thomas Roth Max Mineral Naked Broad Spectrum Spf 45

Max Mineral Naked Broad Spectrum Spf 45 (Discontinued)

An all-mineral, cast-free, lightweight broad-spectrum SPF 45 lotion.
Uploaded by: geekyposh on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Zinc Oxide (19.24%) sunscreen 0, 1 goodie
Titanium Dioxide (1.93%) sunscreen, colorant goodie
Water/Aqua/Eau solvent
Butyloctyl Salicylate solvent
C9-12 Alkane solvent
Carthamus Tinctorius (Safflower) Seed Oil antioxidant, emollient 0, 0-2 goodie
Dicaprylyl Carbonate emollient
Isodecyl Neopentanoate emollient
Cetyl Alcohol emollient, viscosity controlling 2, 2
Coco-Caprylate/Caprate emollient
Propanediol solvent, moisturizer/​humectant
Ethylhexyl Olivate
Glyceryl Stearate emollient, emulsifying 0, 1-2
Peg-100 Stearate surfactant/​cleansing, emulsifying 0, 0
Cetearyl Olivate emulsifying goodie
Cetearyl Phosphate
Triethoxycaprylylsilane
Phenoxyethanol preservative
Sorbitan Olivate emulsifying goodie
Oleth-3 Phosphate surfactant/​cleansing, emulsifying 2, 2
Hdi/Trimethylol Hexyllactone Crosspolymer
Peg-8 Dimethicone emollient
Alumina viscosity controlling, abrasive/​scrub
Xanthan Gum viscosity controlling
Polymethylsilsesquioxane
Polyhydroxystearic Acid emulsifying
Disodium Edta chelating
Squalane skin-identical ingredient, emollient 0, 1 goodie
Gluconolactone exfoliant, chelating superstar
Isopropyl Titanium Triisostearate emollient, emulsifying
Sodium Benzoate preservative
Hydrogen Dimethicone
Potassium Sorbate preservative
Silica viscosity controlling
Mica colorant
Ascorbic Acid antioxidant, skin brightening, buffering superstar
Octyldodecanol emollient, perfuming
Retinyl Palmitate cell-communicating ingredient 1-3, 1-3
Sodium Propoxyhydroxypropyl Thiosulfate Silica
Tocopheryl Acetate antioxidant 0, 0
Diamond Powder abrasive/​scrub
Iron Oxides (Ci 77491, Ci 77492, Ci 77499) colorant 0, 0

Peter Thomas Roth Max Mineral Naked Broad Spectrum Spf 45
Ingredients explained

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

When it comes to sunscreen agents, Zinc Oxide is pretty much in a league of its own. It's a physical (or inorganic) sunscreen that has a lot in common with fellow inorganic sunscreen Titanium Dioxide (TiO2) but a couple of things make it superior even to TiO2.

If physical sunscreens don't tell you anything, go ahead and read about the basics here. Most of what we wrote about Titanium Dioxide is also true for Zinc Oxide so we will focus here on the differences. 

What-it-does: sunscreen, colorant

Titanium Dioxide is one of the two members of the elite sunscreen group called physical sunscreens (or inorganic sunscreens if you’re a science geek and want to be precise).

Traditionally, UV-filters are categorized as either chemical or physical. The big difference is supposed to be that chemical agents absorb UV-light while physical agents reflect it like a bunch of mini umbrellas on top of the skin. While this categorization is easy and logical it turns out it's not true. A recent, 2016 study shows that inorganic sunscreens work mostly by absorption, just like chemical filters, and only a little bit by reflection (they do reflect the light in the visible spectrum, but mostly absorb in the UV spectrum).

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. 

What-it-does: solvent

A nice, multi-functional helper ingredient that's especially useful in sunscreens. It can solubilize some commonly used UV-filters like Oxybenzone or Avobenzone and it can also help to increase the SPF rating of sunscreens. It's also cosmetically elegant, has excellent spreadability and a pleasant, moisturizing skin feel. Oh, and according to Wikipedia, it even helps to stabilize famously unstable UVA-filter, Avobenzone.

What-it-does: solvent

We don't have description for this ingredient yet.

Also-called: Safflower Seed Oil | What-it-does: antioxidant, emollient | Irritancy: 0 | Comedogenicity: 0-2

The oil coming from the seeds of the yellow flowered safflower plant. Similar to other plant oils, it's loaded with nourishing and moisturizing fatty acids: it's a high linoleic acid oil (70%) and has only smaller amounts of oleic acid (11%) (this might be great for acne-prone skin). It also contains antioxidant vitamin E (44mg/100g alpha-tocopherol).

What-it-does: emollient

A clear, colorless, almost odorless oil that spreads nicely and easily and gives a velvet dry skin feel. It is good friends with sunscreen agents and helps to solubilize them. Also, it makes sunscreens feel lighter and spread easier. 

What-it-does: emollient

A  low molecular weight dry, silky emollient ester that gives a light and non-greasy feel to the formulas. It's great at reducing the oily or heavy feeling caused by certain ingredients such as sunscreen agents or pigments. It also gives improved emolliency, spreadability and a smooth, elegant feel on the skin.

What-it-does: emollient, viscosity controlling, emulsion stabilising | Irritancy: 2 | Comedogenicity: 2

A so-called fatty (the good, non-drying kind of) alcohol that does all kinds of things in a skincare product: it makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier). Can be derived from coconut or palm kernel oil.

What-it-does: emollient

A light emollient ester (C8-10 fatty acids connected to C12-18 fatty alcohols) that absorbs quickly and leaves a dry but silky finish on the skin. In terms of skin feel, it is similar to Dicaprylyl Carbonate, another commonly used light emollient. 

Also-called: Zemea | What-it-does: solvent, moisturizer/humectant

Propanediol is a natural alternative for the often used and often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved. 

It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. 

We don't have description for this ingredient yet.

What-it-does: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

What-it-does: surfactant/cleansing, emulsifying | Irritancy: 0 | Comedogenicity: 0

A very common water-loving surfactant and emulsifier that helps to keep water and oil mixed nicely together. 

It's often paired with glyceryl stearate - the two together form a super effective emulsifier duo that's salt and acid tolerant and works over a wide pH range. It also gives a "pleasing product aesthetics", so no wonder it's popular.

Also-called: Part of Olivem 1000 | What-it-does: emulsifying

An ester that comes from Cetearyl alcohol and the fatty acids of olive oil. It often comes to the formula coupled with Sorbitan Olivate as the two together form the well-known, natural emulsifier trade named Olivem 1000. 

Other than helping oil and water to blend, the main thing of Olivem 1000 is generating liquid crystal structures that are similar to the lipid structures of the stratum corneum (the outermost layer of the skin). Thanks to this, Olivem 1000 doubles as an active ingredient with significant moisturizing, barrier-repairing and soothing properties.

We don't have description for this ingredient yet.

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. 

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. 

Also-called: Part of Olivem 1000 | What-it-does: emulsifying

An ester coming from sorbitol and the fatty acids of olive oil. It is part of the popular emulsifier trade named Olivem 1000 that is well-known for generating biomimetic liquid crystal structures. We have more info on Olivem 1000 at Cetearyl Olivate >>

What-it-does: surfactant/cleansing, emulsifying | Irritancy: 2 | Comedogenicity: 2

A partly water, partly oil soluble molecule created by the attachment of (ethoxylated) oleyl alcohol (oil-soluble part) and phosphoric acid (water-soluble part). 

It works as an emulsifier helping water and oil to mix and as a dispersing agent helping insoluble solid particles (such as mineral UV filters or pigments) to be evenly dispersed in cosmetic formulas.  

A handy spherical powder that's often combined with fellow spherical powder, Polymethylsilsesquioxane to form a high-performing texturizing duo. The duo is claimed to provide excellent slip, fluidity and overall skin feel and gives soft focus and wrinkle correction to the formula. It also has strong de-tackifying and anti-caking properties. 

What-it-does: emollient

A water-soluble silicone (silicones are normally oil soluble) that makes your skin nice and smooth (aka emollient) and improves cushion, texture, and slip in the formula. 

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.

It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range. 

Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415). 

spherical texturizing powder that's used as a texture enhancer and soft focus agent. It's claimed to give silicone type softness to the formula and also works as a (temporary) wrinkle filler. 

What-it-does: emulsifying

A so-called dispersant or dispersing agent that's used in inorganic (titanium dioxide/zinc oxide based) sunscreens or in make-up products to help to distribute the pigments nicely and evenly on the skin. It's also claimed to increase the UV absorption of the sunscreen formula as well as to reduce the annoying white cast left behind by inorganic sunscreens.

What-it-does: chelating

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.

Squalane - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 1

It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated  (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life. 

It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.

Gluconolactone - superstar
What-it-does: exfoliant, chelating
  • It’s a polyhydroxy acid (PHA), that is often referred to as next generation AHA
  • It gently lifts off dead skin cells form the skin surface making skin smooth and even
  • In the long term it provides anti-aging benefits, like increased skin thickness and decreased wrinkles (though a tad less than even more proven superstar AHAs)
  • It’s a great moisturizer and even helps to repair impaired skin barrier
  • It’s antioxidant, and does not make your skin more sensitive to the sun
  • It can be used even if your skin is very sensitive, rosacea prone or if you are post cosmetic procedure
Read all the geeky details about Gluconolactone here >>

What-it-does: emollient, emulsifying

We don't have description for this ingredient yet.

What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi. 

It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.

A silicone molecule that is half-way between Dimethicone and Methicone, meaning that some of the methyl (-CH3) groups are replaced with a hydrogen atom (in Methicone half of the CH3 groups are replaced). This makes Hydrogen Dimethicone a handy pigment bonding agent used for the hydrophobization treatment of powders as the H atoms can absorb traces of water from the surface of pigments.

It almost always comes stuck together with either Titanium Dioxide, Zinc Oxide or Mica. In suncare products, it binds to physical UV filters to maximize their protection while minimizing any white casts. It also has good chemical stability with no irritation. In makeup, it is often paired with Mica where it offers nice hydrophobic properties and improves skin adhesion - meaning it will make it easier for products to stay where they should be.

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.

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. 

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. 

Ascorbic Acid - superstar
Also-called: Vitamin C, L-ascorbic acid | What-it-does: antioxidant, skin brightening, buffering
  • Works best between a concentration of 5-20%
  • Boosts the skin’s own collagen production
  • Fades pigmentation and brown spots
  • If used under sunscreen it boosts its UV protection
  • Extremely unstable and oxidizes very easily in presence of light or air
  • Stable in solutions with water only if pH is less than 3.5 or in waterless formulations
  • Vit E + C work in synergy and provide superb photoprotection
  • Ferulic acid doubles the photoprotection effect of Vit C+E and helps to stabilize Vit C
  • Potent Vit. C serums might cause a slight tingling on sensitive skin
Read all the geeky details about Ascorbic Acid here >>

What-it-does: emollient, perfuming

A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.

Also-called: Form of Retinoids | What-it-does: cell-communicating ingredient | Irritancy: 1-3 | Comedogenicity: 1-3

It's an ester form of vitamin A (retinol + palmitic acid) that belongs to the "retinoid family". The retinoid family is pretty much the royal family of skincare, with the king being the FDA-approved anti-aging ingredient tretinoin. Retinol is also a very famous member of the family, but it's like Prince George, two steps away from the throne. Retinyl palmitate will be then Prince Charlotte (George's little sister), quite far (3 steps) away from the throne. 

By steps, we mean metabolic steps. Tretinoin, aka retinoic acid, is the active ingredient our skin cells can understand and retinyl palmitate (RP) has to be converted by our metabolic machinery to actually do something. The conversion is a 3 step one and looks like this:

We don't have description for this ingredient yet.

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: abrasive/scrub

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. 

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

what‑it‑does sunscreen
irritancy, com. 0, 1
A physical/inorganic sunscreen with the broadest spectrum (UVB and UVA II, less good at UVA I) protection available today. It also has good stability and also works as a skin protectant, anti-irritant. Might leave some whitish tint on the skin, though. [more]
what‑it‑does sunscreen | colorant
A physical/inorganic sunscreen with pretty broad spectrum (UVB and UVA II, less good at UVA I) protection and good stability. Might leave some whitish tint on the skin, though. [more]
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 solvent
Multi-functional helper ingredient in sunscreens. It can solubilize and stabilize commonly used UV-filters and has a cosmetically elegant, emollient skin feel. [more]
what‑it‑does solvent
what‑it‑does antioxidant | emollient
irritancy, com. 0, 0-2
Safflower Seed Oil - emollient plant oil with moisturizing fatty acids (linoleic: 70%, oleic: 11%) and antioxidant vitamin E (44mg/100g alpha-tocopherol). [more]
what‑it‑does emollient
A clear, colorless, almost odorless oil that spreads nicely and easily and gives a velvet dry skin feel. It is good friends with sunscreen agents and helps to solubilize them.
what‑it‑does emollient
A  low molecular weight dry, silky emollient ester that gives a light and non-greasy feel to the formulas. [more]
what‑it‑does emollient | viscosity controlling
irritancy, com. 2, 2
A fatty (the good, non-drying kind of) alcohol that makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier).
what‑it‑does emollient
A light emollient ester (C8-10 fatty acids connected to C12-18 fatty alcohols) that absorbs quickly and leaves a dry but silky finish on the skin. In terms of skin feel, it is similar to Dicaprylyl Carbonate, another commonly used light emollient.  [more]
what‑it‑does solvent | moisturizer/humectant
A natural corn sugar derived glycol. It can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. [more]
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1-2
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
what‑it‑does surfactant/cleansing | emulsifying
irritancy, com. 0, 0
A commonly used water-soluble surfactant and emulsifier. [more]
what‑it‑does emulsifying
Part of Olivem 1000, a natural emulsifier duo that is known for forming biomimetic liquid crystal structures. It doubles as an active ingredient with barrier repairing and soothing properties. [more]
A clear, light yellow liquid that is used to coat pigments (such as inorganic sunscreen agents or colorants) in cosmetic products.  [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 emulsifying
An ester coming from sorbitol and the fatty acids of olive oil. It often comes to the formula coupled with Cetearyl Olivate and the two together help water and oil to blend (emulsifier). It's a natural and Ecocert approved duo.
what‑it‑does surfactant/cleansing | emulsifying
irritancy, com. 2, 2
A partly water, partly oil soluble molecule created by the attachment of (ethoxylated) oleyl alcohol (oil-soluble part) and phosphoric acid (water-soluble part). It works as an emulsifier helping water and oil to mix and as a dispersing agent helping insoluble solid particles (such as mineral UV filters or pigments) to be evenly dispersed in cosmetic formulas. [more]
A handy spherical powder that gives excellent slip, fluidity and overall skin feel to the formula (often combined with Polymethylsilsesquioxane). [more]
what‑it‑does emollient
A water-soluble silicone (silicones are normally oil soluble) that makes your skin nice and smooth (aka emollient) and improves cushion, texture, and slip in the formula.  [more]
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]
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
A spherical texturizing powder that's used as a texture enhancer and soft focus agent. [more]
what‑it‑does emulsifying
A dispersing agent that's used in inorganic (titanium dioxide/zinc oxide based) sunscreens or in make-up products to help to distribute the pigments nicely and evenly on the skin. [more]
what‑it‑does chelating
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 skin-identical ingredient | emollient
irritancy, com. 0, 1
An emollient and natural moisturizer that can be found also in the sebum (oily stuff our skin produces). It leaves a nice non-greasy, non-heavy feeling on the skin. [more]
what‑it‑does exfoliant | chelating
A next generation AHA, a so-called PHA that gently exfoliates skin without irritation. It also moisturizes and helps the skin barrier. It also has antioxidant properties. [more]
what‑it‑does emollient | emulsifying
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [more]
A silicone molecule that is half-way between Dimethicone and Methicone, meaning that some of the methyl (-CH3) groups are replaced with a hydrogen atom (in Methicone half of the CH3 groups are replaced). [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 viscosity controlling
A white powdery thing that can mattify the skin and thicken up cosmetic products. [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 antioxidant | skin brightening | buffering
Pure Vitamin C. A skincare superstar that is clinically proven to boost collagen production (in 5-20% concentration), fade hyperpigmentation and boost UV protection under sunscreen. Also, it's extremely unstable and hard to formulate. [more]
what‑it‑does emollient | perfuming
A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.
what‑it‑does cell-communicating ingredient
irritancy, com. 1-3, 1-3
An ester form of vitamin A (retinol + palmitic acid) that is pretty much the least effective member of the retinoid family. Its anti-aging effects are quite questionable as well as its behavior in the presence of UVA light. (Use it at night if possible!) [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 abrasive/scrub
what‑it‑does colorant
irritancy, com. 0, 0
A mix of red, yellow and black iron oxide. [more]