Thanks for the query
sometimes black toe even happens due to mild repeated trauma,
This can be even with trauma with shoe.
As you dont have pain or any other symptoms,
There is nothing much to worry.
Just apply some keratolytic
cream like salicylic cream.
There wont be need of amputation
Let me know if you have any other doubts.
you can ask a direct question to me on this forum, following the below link.
Wishing you good health.