Mica is what gives makeup those lovely flecks of sparkle. It can also make concealer appear more natural. But what exactly is mica and how does it work? And is it safe?
[Read More: How Does “Intelligent” Matching Makeup Work?]
What is Mica?
Mica is the term for 34 types of layered or flaky phyllosilicate minerals, or minerals containing silica (USGS). Mica likely got its name from Latin, where the word “micare” means to shine. Many believe that mica’s name origins refer to its lustrous qualities (Mineral Information Institute).
Flake Mica in the United States comes from Arizona, Georgia, New Mexico, North Carolina, South Caroline, and Dakota — with more than half of all mica comes out of North Carolina. It can be mined from a metamorphic rock, called schist, or as a by-product in the processing of kaolin and feldspar. Depending on the type of rock that mica comes from, there are different color properties.
Mica has numerous industrial purposes, those being its primary usage. However, it’s frequently used in and known by many FutureDerm readers as something found in makeup.
Mica in Makeup
By covering flecks of mica in titanium dioxide, the pearlescent product can reflect all the colors of the rainbow. Adding in iron dioxide can help to craft earthier and more gold hues (SPC). Different particle sizes can help makeup manufacturers offer consumers different looks, from a silky satin sheen to something that appears more glittering. Size can also affect the color; at various nanometers mica can emit red, blue, green, etc. light (Cosmetic Dermatology). Barium chloride and sodium sulfate can help to take away some of the extra glossy look.
While pearlescence from mica is aesthetically pleasing and is often thought of as something that adds an illuminating touch, there’s practical application in including it in makeup. Often, makeup can appear very flat and adding something iridescent can create depth and give wearers a move “alive” look (L’Oreal).
With the right formulating, mica can create and effervescent glow. But even better, well-crafted mica in the right size and with the proper additions, helps to correct face shape, making it valuable in makeup intended to hide fine lines. In fact, it can be used to add contouring and highlighting to the face that looks natural, as well as to make heavily applied makeup intended to cover something appear more natural (Journal of the Clay Society of Japan).
Mica Makeup Safety
Mica is primarily dangerous when inhaled, so it’s generally any powder or aerosol products that are the most concerning. The particles can get into the lungs and cause scarring. In addition to this, mica can cause pneumoconiosis, which causes increases lung and breathing problems as it progresses (CDC, Occupational and Environmental Medicine).While safety guidelines generally focus on those who are working around mica in an industrial setting.
And titanium dioxide, with which mica is often mixed, is safe for skin but can be carcinogenic when inhaled, as shown in tests on mice and hamsters (Toxicology and Epidemiology).
As aforementioned, danger with these ingredients comes primarily with inhalation. So, it’s when they’re inhaled via powder or aerosol formulas that they could pose a risk to lungs.
Mica is a phyllosilicate mineral that has numerous uses in makeup. It can help to create shine and color, but is also useful for creating natural looking and “alive” makeup that can be used for better coverage and contouring. Unfortunately, in powder and aerosol form it can be inhaled and while there aren’t studies on how this affects lungs.