Yep, there is gray and red grit. Gray grit is usually just crushed granite but may have oyster shell too. Red grit is granite (to help crush food), oyster shell (for calcium), and charcoal (detox benefits). The pink powder that coats the 'red grit' is just a bunch of other minerals they wouldn't normally get by eating normal food and grit. I'll see if I can find the ingredients label.
My birds love red grit (maybe because it's the only kind I give them?). If they run out of food, water, and grit at the same time, and you fill each back up, they will go for the grit first everytime. They might be starving to death, but they've got to eat those yummy rocks
I have seen some red chick grit before, but not often. I still give it to our doves and there's actually a good amount of small pieces that they can handle. You can always put it in a cloth and beat it into smaller pieces with a hammer.
But whatever you use, be sure you have oyster shell. Calcium is extremely important. Granite is the next important since it helps them digest stuff, but it's not as mandatory for their health, as they do have gizzards that work for the same purpose.
Here's the ingredients for one of the red grits. I'm sure it'll differ depending on who makes it:
manganese oxide, copper oxide, calcium carbonate, granite grit, salt, charcoal, anise oil, zinc oxide, calcium iodate, ferrous carbonate, cobalt carbonate, oyster shell, and iron oxide.
I'm pretty sure mine has all of that and some things I had a tough time pronouncing, LOL. But either way, it smells like licorice from the anise oil.