I've explained this all before.
1. If you see coins with discolored reverses, usually stripped darken, they were in Folders.
2. That shinny surface on the back of the slots is left over glue from the manufacturing process.
3. Kids usually like that glue since if they put a well worn coin in the slot, spitting on that glue reactivates it and makes the coins stay in place.
4. The reason it is hard to put the coins into the slots is they are purposely tapered so that the front of the slot is smaller than the back. This is to help hold the coins in place.
5. The way people push those coins into the slots is usually with their thumbs or some even use a hammer. Your thumbs are full of moisture, acids, oils and that is now on the coins.
6. No seeing the reverses too makes coin collecting a little less appealing.
7. Removing the coins usually ends up putting a finger right through the back and ruining what is already a useless Folder.
8. Without any protection from scratches, moisture, dirt, fingers, etc. on the coins in a Folder, they usually end up much worse than when put in place.
Other than the above, Folders are OK I guess.
1. If you see coins with discolored reverses, usually stripped darken, they were in Folders.
2. That shinny surface on the back of the slots is left over glue from the manufacturing process.
3. Kids usually like that glue since if they put a well worn coin in the slot, spitting on that glue reactivates it and makes the coins stay in place.
4. The reason it is hard to put the coins into the slots is they are purposely tapered so that the front of the slot is smaller than the back. This is to help hold the coins in place.
5. The way people push those coins into the slots is usually with their thumbs or some even use a hammer. Your thumbs are full of moisture, acids, oils and that is now on the coins.
6. No seeing the reverses too makes coin collecting a little less appealing.
7. Removing the coins usually ends up putting a finger right through the back and ruining what is already a useless Folder.
8. Without any protection from scratches, moisture, dirt, fingers, etc. on the coins in a Folder, they usually end up much worse than when put in place.
Other than the above, Folders are OK I guess.



















