Why Mica is a Must
There are a few mineral-based ingredients that even hard-core, plant-based-ingredient-loving people like me will happily include on the list of 'exceptions to the plant-based rule'. One of these is mica. Mica is quite simply a must-have.
You: how can some rock be a must-have?
Me: Think eyeshadow.
Are you with me now?
Good! Because today we're celebrating mica and all of its fabulous versatility!
Glittery Crumbs
The word mica is derived from Latin and means 'a crumb'. The name is also so similar to the word micare (which means 'to glitter') that you can't help thinking they're somehow related. |
| Muscovite - also known as common mica |
Mica – The Group
The mica group actually encompasses 37 minerals – all with a layered, sheet-like, or plate-like texture and a slew of impressive properties, like:- elastic
- flexible
- resilient
- hydrophilic (capable of interacting with water)
- refractive (throws light around in a shiny, lovely, colorful way)
- reflective
- ranges in opacity from transparent to opaque
There's actually much more, but I was afraid you might think I was exaggerating.
I'm not.
Really.
Really.
Preparing For Use
Depending on the desired end use, mica is treated in different ways, for example:
Dry-ground mica will be used as filler in gypsum sheets for drywall, in drilling fluids, as an additive in rubber, as a component of roof shingles, in heat shields, and much more.
Dry-ground mica will be used as filler in gypsum sheets for drywall, in drilling fluids, as an additive in rubber, as a component of roof shingles, in heat shields, and much more.
Wet-ground mica is, among other things, used for pearlescent paints, as an insulator in concrete blocks, as a durability-increasing additive to axel grease, or – here comes the fun part – in lipstick, nail polish, blush, foundation, and eyeshadow.
Depending on the size of the mica particles (and any added coating), the shine-factor will be more reflective and transparent, or more opaque and less lustrous.
Pearlized, Shiny, Opaque, or Translucent
Depending on the size of the mica particles (and any added coating), the shine-factor will be more reflective and transparent, or more opaque and less lustrous.
One wouldn't think it possible to coat tiny flakes of mica, but this is exactly what is done to mica used for pearlized make-up colors. The coating is often a metal oxide (for example iron oxide or titanium dioxide). By combining different metal oxides and adjusting the thickness of coated layer, a wide range of pearlescent pigments can be created.
In short, just about every make-up color you find includes mica in one form or another.
In short, just about every make-up color you find includes mica in one form or another.
Is it Safe?
Yes. It's safe. Find more info at this page ar CosmeticsInfo.org as well as this page at CosmeticsInfo.org. And here is a link to an FDA chart with list of color additives permitted for use in cosmetics.Size Matters
For an overview on mica particle sizes, check this info (from DIY Cosmetics)
Particle Size 2-25 µm = silky luster and strong hiding powder
Particle Size 10-60 µm = pearl luster with medium hiding power
Particle Size 10-125 µm = shimmering luster and low hiding power
Particle Size 20-150 µm = sparkling luster and transparent
Particle Size 45-500 µm = glittering luster and very transparent
Photo of Muscovite from Wikipedia
COLOR EFFECT vs. PARTICLE SIZE
Particle Size 15 µm or less = low luster, good hiding powerParticle Size 2-25 µm = silky luster and strong hiding powder
Particle Size 10-60 µm = pearl luster with medium hiding power
Particle Size 10-125 µm = shimmering luster and low hiding power
Particle Size 20-150 µm = sparkling luster and transparent
Particle Size 45-500 µm = glittering luster and very transparent
Photo of Muscovite from Wikipedia
Comments
Your question is very timely, as I am working on a bit of research into the use of metals and minerals in make-up and plan on doing a post on this before long (don't take that literally-- sometime 'before long' turns out to be a year if that's where the research takes me)-
Meantime, I can recommend DIY cosmetics as a reliable source of both product- but also information.
But- to give you a bit of an immediate reply - I checked the FDA page - which says micas are exempt but still must comply when used in cosmetics---
Quote:
"Colors exempt from certification. These color additives are obtained primarily from mineral, plant, or animal sources. They are not subject to batch certification requirements. However, they still are considered artificial colors, and when used in cosmetics or other FDA-regulated products, they must comply with the identity, specifications, uses, restrictions, and labeling requirements stated in the regulations [21 CFR 73]."
Find the page here
http://www.fda.gov/ForIndustry/ColorAdditives/ColorAdditivesinSpecificProducts/InCosmetics/ucm110032.htm
I hope this was of some help!