Jewel and Stone are required items for getting a card through Card Trader. In order to get those items, you need to exchange cards with the same rarity and same attribute as the ones that you want to acquire or meet "Stage" requirements.
Jewels and stones are one of the duel rewards. Basically, having a lots of duels and scoring high are ways to earn those items since you can get one reward by 1,000 score. For example four rewards appear when your score is 4,000 or more and less than 5,000.
You can convert your cards into jewels and stones at the Card Catalog. What trader item you get is based on attribute and rarity of a card you convert. For example, a normal rarity spell card can be exchanged with 100 gold and a Stone of Spell.
Jewels and stones are also reward for completing some missions, although you cannot obtain many of those items by doing that.
|Jewel||How to get|
|Stone||How to get|
|1. Low stats normal monster card|
|Monster cards that have low ATK without effect are useless. Since you do not have to keep such cards, they will be the first to be exchanged with trader items.|
|2. Cards obtained by purchasing pack|
|Cards from a pack can be obtained again while the pack is purchasable.|
|3. Common cards from Card Trader|
|Only gold is needed to trade with common rarity cards, and those cards become subject to trade repeatedly.|
|1. Level reward cards|
|You may not be able to see cards that are reward for leveling-up characters once you lose them, since no other ways to get such cards are confirmed.|
|2. UR/SR cards from Card Trader|
|There is no reason to turn UR/SR cards that you get through Card Trader back to trader items again.|