For this test, I used the Rimmel London Lasting Finish Blendable Powder Blush in Santa Rose (for no reason other than that the packaging is super lightweight, meaning my scale won't get mad at me for using it). It's a lovely peachy rose that is light enough to look great on fair skin.
I applied this blush ten times to ensure that I had a decent mean from which to calculate.
The raw data for each use is shown below:
|A single application of this blush looks like this on my cheeks.|
The generalizability of this result is pretty unclear. I speculate that women with darker skin will probably need to have a slightly heavier hand on blush application than women with lighter skin, and the variability in blush pigmentation will almost certainly affect how much use you get out of any given product.
However, assuming that this mass remains relatively consistent across blushes and humans, you can use these findings to calculate an estimated number of uses for any blush you love. For example, at 0.25oz/7.08g for $28, Benefit's Dandelion should last about 506 applications, costing you five and a half cents per use. NARS Orgasm, at 0.16oz/4.5g for $29, might last 321 applications, ringing it at over nine cents per use.