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Really, how come they use it in every other matte finish they sell, but not this one? Silica has been the cheap and easy route to matte finishes for a very long time. You will find references everywhere to avoid matte finishes if durability is going to be an issue for the reasons I stated. There is silica in all of their matte finishes. It does not have to be listed on the MSDS because it is considered inert and is covered under nondisclosure rules of proprietary mixtures.
Sitka, I took a closer look at the MSDS for the Krylon flat clear sealer and I see that indeed there is +/- 3% Amorphous Silica in the mix. You were correct on this and I stand corrected. Amorphous Silica is a hazardous substance with an OSHA exposure limit and is listed on the MSDS sheet.
I have not found references "everywhere" to avoid matte finishes. In fact, they exist for a reason and are common. When I use this finish on a painted stock I typically apply 5-6 light coats and have never had issues with it wearing off; if it did it is a simple matter to re-apply.
