What is difference between 24 lb bond vs. 60 lb offset paper?
24 lb paper and 60 lb offset paper is exactly the same paper! See below charge for weight comparison. They have the same thickness, texture and weight. Their manufacturing process is slightly different, and that is why they are called differently.
Also, 100 lb gloss cover, common paper used for postcard and flyers, is equivalent to 11 point stock.