Well, what I know is that there is this kind of hotfix rhinestone / iron-on rhinestone that you can easily buy online. These kind of stones are flat on the back and have special glue, which can melt with the heat of an iron. It is normally dry and get melted and sticky at around 350F.
This kind of stones are easier to handle as the glue won't get messy and sticky everywhere.
U can have a try!
Hope above is helpful!!
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