One interesting aspect of buying a jersey is the material from which it was made. The question on many peoples' lips is: "Is jersey fabric thick?" The answer, in short, is: "it depends". If we were to look at a few different brands like , we would see that each manufacturer uses various materials, and that the differences in the thicknesses of these fabrics are slight, but significant enough to make a noticeable difference in the quality of your purchase.
Two of the most popular fabrics for knitted or crocheted products are cotton and polyester. Cotton has many great qualities, including being extremely comfortable, great for those who enjoy playing outdoor sports (think of your Nascar shirt), and the fact that it is naturally flame retardant. Another positive trait of cotton is that it is a very renewable resource. If you were to produce more cotton plants, then more cotton fabric would be produced, which would reduce the negative impact on the environment. While there are some major disadvantages to using cotton fabric for making your apparel, the positives definitely outweigh them.
Polyester is a very high tech fabric, as its properties are nearly identical to nylon, yet are way less expensive than nylon (which is why polyester is often used for making sports jerseys). The biggest difference between jersey fabrics, then, would be the amount of "thickness" (or weight) which is present in the product. A higher amount of thickness in a fabric means that it is taffeta, a finer woven fabric which would look and feel similar to the sheets in your grandmother's old bed. Many companies producing athletic garments use high quality taffeta for their products, and the quality of the taffeta will also be reflected in the price, sometimes making high-quality t-shirts a lot less expensive than comparable cotton/polyester blends.