Updated: Sep 2
There are a variety of Mica Powders, Pigment Powders & mixes of both, & hopefully the information below can help when determining what you want to use, when adding to your various resin projects.
Sometimes mica powders & pigment powders terminology gets used interchangeably. But they’re actually not the same thing. Powders are pigments or mica powder or a mix of both, (which are particles that will be suspended in the medium, such as is used with resin or various acrylic mediums).
Mica is sparkly. Pigment powder itself, is matte. They behave differently. But they’re also sometimes mixed together in the same package to achieve different looks. And that can mean the powder you bought won’t work quite the same as you expect. If it’s has more Mica, it will colour less then if it has more pigment added.
Mica is a natural stone mineral with shiny flakes, that often gets ground into a powder for Mica powder. The shiny in the flakes is why Mica powders are more sparkly. They’re often used to give a metallic or shimmery pearl-like effects.
Mica powders do often have some colour, but on their own, they’re not optimal for colouring things because their main purpose is to create sparkle or shine. Mica powders can not create a solid wash of bright colour on their own.
Pigment powders are ground-up colours. Pigments are the actual colours themselves, and they’re often called by their more common names like ultramarine blue, cadmium red, yellow ochre, and titanium white. There are also (less expensive) artificial pigments with different names such as Pigment Blue 15. Pigments are what manufacturers use to give paint its colour. They are not shiny & sparkly. Pure artist’s pigments (pure colour) are actually fairly expensive, so pigments you buy from cheaper sellers online are usually mixed with fillers (such as chalk) that make the color go farther.
It can be a bit confusing because in more recent years the word pigment, occasionally gets referred to as mica and synthetic mica particles. Therefore it can be said that mica is a type of pigment, but pigments are not mica. In reality, these materials are two different things and are very dissimilar materials.
Interference pigments are synthetic Mica & they have a special coating on them. Chameleon powders also have a special coating on them which reflects the light with multiple colors depending on the angle of the light.
Pearl mica powder typically is uncolored, which is the same as white or silvery. But mixing pigment with mica powder just results in a mix of pigment and mica. The mica itself will not become coloured.
If you’re unsure about the Colour you want, & there is no description where you purchased it, you nay need to do a test with it first. Or contact the seller to see if you can find out more if it’s considered a matte (which is more opaque in resin if using enough), or if it’s more transparent.
Some mica powders are just made to be more transparent, & you may need to add more of said powder to get deeper colour saturation. Keep in mind the important resin to colour ratio. Typically the suggested ratio of colourants is 2-10% to resin, or if using more it can upset the chemical balance of resin effecting its cure (& also cause premature exotherm). Sometimes adding a pigment will be needed, if there is a desire to change transparency level of a colour.
Although we are a resin art supply store, (for those who aren't aware), our micas & pigment powders can be used in acrylic mediums as well. See separate blog post for more info.
Sometimes people suggest using eyeshadow for colourants in resin. While this can sometimes work, it is not pure pigment. It will take a lot more powder to achieve pure pigment depth, so you'll need to watch your ratios. Also, some eyeshadows may have other ingredients (moisturizer or oils) added that are not resin friendly. Also test on small projects first.
There is a Colour Passion Blog as well with a bit of information about their pigments, pastes, tints & glitters. If you're wondering about the difference between Colour Passion Base Cell White Paste & Top Cell White Paste, it's discussed in that blog.
There is also a Le'Rez Expressions Blog, with some information that might come in handy. If you have a paste that has solidified (hardened/thickened), there is tips on how to soften the pastes again, plus a link to a quick youtube video about that (from the creator of Le'Rez Expressions). There's great information about how versatile the transparent inks are, and information about the fact these can be used in other mediums besides resin art too.