Grigio Nimbus vs Florett Silver

Grigio Nimbus actually shares it roots with Florett Silver, since being under the same ownership Lamborghini has adopted quite a few of Audi's paint codes often giving them their own Italian name.
But if you look closely you might notice in these images they are not identical, that's because they don't share the same paint code. The R8 is painted with the latest variant of Florett Silver L5L5, while the Huracan uses the older LZ79.

The difference is minimal but the silver on the R8 is slightly brighter and more pure while the Huracan seems to have an ever so subtle darker undertone.
This is something you'll only notice when seeing them side by side as the difference is so minor.