You can easily tell by touching them and there usually is a sheen on higher quality cotton due to the length of the fibers in the yarn. These will also shrink less because the tiny fibers don’t crimp up as much. If looking online, read the descriptions. The more informative they are about the actual fiber and content, the better the chance of them offering you quality, unless they have a really good copywriter that glamorizes even basic materials. Look for words like ‘long staple’, ‘Sea Island’, ‘Egyptian’… whereas words like ‘Fine’, ‘High quality’ don’t mean squat.
Buy this shirt: https://nemoshirt.com/product/lsu-girl-hated-by-many-loved-by-plenty-heart-on-her-sleeve-shirt/
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