I sew leather and wool quite often so I am familiar with the button/snap dilemma. If it was just leather w/o the scales, then I would say button. However I think the preservation of the scales weighs on the snap side.

Here is a tourmaline button with mule deer leather. A foraging bag I made a while back.

The last photo has a beaded patch that I added to cover the bullet hole. ✊🏽🫶🏽

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