OPI Get Your Number (GYN) is a bright blue with holographic glitter and sparkles within the polish and dries very gritty like rough sand.
The texture of these polishes are absolutely 100% different. The OPI is soo coarse that it could pull a sweater while the Zoya definitely would not. Nyx truly feels like a fine grit nail file with a consistently bumpy feel to it. GYN has smaller and larger particles that can be compared to sugar in the raw granules.
Personally, I loved the OPI Liquid Sand, I couldn't stop touching my nails! GYN is my choice from these two, because of the true gritty texture, the significant sparkle and the bright color. Nyx seemed a bit dull in comparison although there were bits of shimmer and sparkle it was no where near as prominent as GYN.
OPI Liquid Sand is part of the 2013 Mariah Carey Collection and can be picked up for $9 USD. There are four different colors with this Liquid Sand texture however they are all slightly different in style.
The Zoya Pixie Dust Collection can be found on Zoya.com for $9 USD and there are six different choices all with the same look and feel.