The crystal shard deals 1 damage and penetrates 1 layer of shield. The shard can be intercepted by defense drones, and is only generated when the hull is damaged. The shard must make the killing blow to the enemy ship. This can be done easily one of two ways:
1. If the shard causes the damage that makes the enemy ship offer surrender, this will count. That is only if the surrender is accepted.
2. Jump around until you find an enemy ship with one or fewer shields and no defense drones. Damage the ship until it only has one HP left, and then drop all of your shields. Obviously it helps to have high hull strength and to leave the enemy weapons functioning. It can be done by leaving the enemy ship at two health, but you will need to take more hull damage to generate two shards.