Here's a little Amy Rose keychain.
This is with her older design, seen on Sonic CD where she has the ruffle skirt and purple shoes. For this little key chain, she's just standing there, though with how it's sculpted she looks somewhat worried.
The chain/clasp are gold-tone which is slightly unusual. However, what's really curious is that this little chain is almost identical (it is likely larger than) the Amy pencil topper which you can see in Japan School Supplies. 

TODO: fix link from japan school supplies to sonic district