Can you use it for concrete, stone or silica dust?

This one deserves a straight no rather than a technically-true yes, so here it is up front: do not use this as your silica respirator on a regulated job.

The physics are fine. Crystalline silica from cutting, grinding or drilling concrete is particulate, and a unit rated EN 12941 TH3 P R SL filters at least 99.95% of particulate. Nothing about stone dust defeats that filter.

The problem is not the filter, it is the paperwork, and on silica the paperwork is the point. Silica exposure is regulated, with required protection factors and written exposure control plans, and those rules are generally written around respirators certified under the US NIOSH scheme. The Breathie Thingy is not NIOSH-certified. It is certified to the European standard EN 12941, which is a real standard and not the one your inspector is holding.

So: cutting a paver in your own garden on a Saturday, it will keep the dust out of your lungs and that is worth a great deal. Running a crew cutting concrete for a living, buy whatever your exposure control plan requires. We would rather lose the sale than have you cite us to a safety officer.

Silica is not like wood dust. The damage is silicosis, it is permanent, and it shows up years later. It is the wrong hazard to be casual about.