What Causes Discoloration And Roughness Of Skin On Using Weightlifting Gloves?

I workout and use weightlifting gloves, but since I have been using them, some of my fingers (pinkie, thumb, and finger next to thumb most affected) are discolored with dark spots. That area also has a rough skin texture that the fingers that are not affected. Any clue what this could be? I have stop wearing the weightlifting gloves.