Hello Pandora,
Some might have a break out to Bismuth Oxychloride which is used in BM. However the mineral makeup that I sell does not contain that..
Bismuth is the by-product of lead and copper refining, as well as other metals.
It is very heavy and chemically resembles arsenic. It has a whitish/iridescent hue and has a very high shine property to it. this heavy metals it is the only non-toxic.
Companies use this in their cosmetics because it is an inexpensive filler. It does have binding qualities, so the makeup will cling to your skin. There are other products that are better for your skin and just as effective as bismuth. The Bismuth will camouflage fine lines, wrinkles and discolorations. You'll notice a nice shiny look after applying the makeup. Not oily, but shimmery. That's bismuth oxychloride.
Wonder why you have to do that heavy buffing step? Well Bismuth is a very heavy element, which makes it difficult for many people to wear. Bismuth has to be forced into the pores. If you don't do the buffing step it will come right off your face. The heaviness can result in clogged pores or irritated skin. Bismuth oxychloride often feels silky when you rub it between your fingers. Mineral makeup companies that do not use it have a lighter feeling makeup that usually blends into the skin better and with less effort.
Bismuth may be a cause of the itchiness some women get when they wear it. Many women experience noticeable itching when they sweat. Now it would make sense that your skin would get irritated.
So Pandora The Bismuth can be the cause of the problem... I will send you a sample..