The very first version of Minty had white stripes mixed in with the pink in her mane, red paint on the candy stripes, and a red hoof heart on the non-magnet (display side) hoof. This was the original version that came in the Promo Packs... the info on the Wiki is wrong, the Promo Pack edition was the first version released. I remember, I was collecting as an adult in my 20's when these first came out and the promo packs were the only way you could get Minty, Butterscotch, Autumn Skye, and Starswirl at first.
Shortly after they first released G3, they changed the hoof heart placement so that the hoof heart was always on the hoof with the magnet. So if your Minty has a red hoof heart on the display (non-magnet) side, she is one of the Promo Pack (first edition) Mintys.