They do look quite the same, so, comparison time!
The polishes are L.A. Girl Rockstar Overdose, and a glitter polish from Claire's, sadly no name on the bottle.
In the bottle they look quite alike:
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After the first layer it's immediately clear the Claire's is not nearly as glittery as the L.A Girl.
This is one layer of each.
On my index finger L.A Girl Overdose, middlefinger Claire's, ringfinger L.A. Girl Overdose, pinky Claire's.
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This is 3 layers. Claire's can not compete with the L.A. Girl as glitteriness goes.
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Last up I put on 2 extra layers of the Claire's polish. It got a little more dense and started to look a bit more like the L.A. Girl Rockstar Overdose. (yeah, sorry, pics are pre-clean up)
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So, Claire's glitter polish is quite similar to L.A. Girl Rockstar Overdose, except it is way less glittery, and that's quite a shame. As colour and look goes, the two are quite similar.
Hope this was fun to read and maybe helpful. Bye for now.