How pieces get in
Purchases you make on GSG are added automatically. You add the others from the Encyclopedia entry with the Add to my collection button, with the price you paid if you want to note it.
Import a file
If you already keep your collection somewhere else, you can import a CSV file, the Numista one or your own. GSG matches each row to its entry and asks you to confirm any doubts.
Identify with a photo
When the GSG app is available, you will be able to add a piece by pointing the camera at the coin.
Today's value
Each piece shows its value today, calculated with Encyclopedia data. It is an indicative figure, not a purchase offer or a recommendation.
Sell from your collection
Each piece has a Sell button. You can publish a listing with the entry already filled in or ask GSG for a direct offer. You can also select several pieces and sell them in bulk.