Laura Mercier Secret Brightening Powder

this is a product that have been raved about over and over again, not only this particular one, but also the product type in general. a fine powder that contains light reflecting particles to use on the under eye area, alone or over cream/liquid concealer to brighten up the under eye area and to conceal any darkness.
i was curious about such products for a long time but have not purchased the Benefit Powderflage (which is the first of this kind that i got to know) yet - i only tried the cheaper version by Alverde. the effect with the Alverde product was not very visible, so i was ambivalent about such powders. are their effect really so little or is it only because i bought a drugstore one?
in the last year i heard many good reviews and recommendations for the Laura Mercier Secret Brightening Powder so now i bought it to try, i was just too curious.
i bought mine in #1 (the light version) on ebay, it contains 4.6g and did cost about 27AU$/~20€.
the amount will last me forever, seeing how little i need to use every time.
it comes in a small simple jar, here you can see my little Laura Mercier powder family for size comparison ;)

the biggest is the Translucent Loose Powder, the medium size is LM Mineral Foundation and the baby jar is the Secret Brightening Powder

it's a very fine and fluffy white-ish powder that feels very smooth and gliding due to the silica and silicones contained in it. it's sheerly white and contains many very fine shimmering bits. applied on my forearm, i could still see the shimmer in bright sunlight but in the shadow it's totally invisible. moving my arm around i could really see how it lightens up the area where i applied the powder in different angles even though it was blended out quite well.

Laura Mercier Secret Brightening Powder in sunlight

Laura Mercier Secret Brightening Powder in the shadow

now on the eye area i would use a fluffy synthetic blending brush to apply it. i use it on top of my undereye concealer to set it and also to give me some extra-brightness. i would only put it on the edge of my dark circles and then blend out. it applies evenly and glides on the skin effortlessly. although looking straight into the mirror the effect is not that apparent at first, i can clearly see that it brightens up this area especially when i'm looking down (where my cirles would be most visible). on the eye area i haven't noticed any shimmer even in different lights. it does set my concealer and doesn't creep into my undereye lines but i don't find it prolonging the wearing time of my concealers that much.
i have also tried it as subtle cheek highlight but don't like the white-ish bright effect as much as a slightly golden regular highlighter, especially in the summer. but i think it can be used on every other area of your face were you struggle with shadows (like sometimes the areas below the corners of my mouth appear darker, or beneath your nostrils).
i don't have very dark under eye circles so i find the effect very nice for me - it will definitely amp up the brightening effect of your regular concealer, but if you suffer from very dark circles i don't think that this is the miracle solution for you to erase all these problems. for deeper skin tones (maybe NC40+ ?) i would recommend the #2 slightly tinted version of this as this one would definitely look ashy on WOC beauties.
all in all a very nice product - the effect is much stronger than of my Alverde equivalent.

here i want to show you its effect worn alone (without concealer but only foundation): i'm wearing it on my right eye (so the left from your perspective) - on the other eye nothing than a bit of blended out foundation.

i think the effect is undeniable, i also like how it smoothes out my under eye area.