Quartz shards collected by the Japanese Government.
Quartz is the nucleus of a Scub Coral and appears whenever a Scub Burst occurs in Eureka Seven: AO. It is shown to have energy producing capabilities, and may be the cause of the fusion explosion that occurs when a Secret collides with the Scub Coral. Generation Bleu's main goal is to collect these Quartz for an unknown purpose; it could be in order to prevent any more Scub Bursts. By removing the Quartz, the trapar waves in the surrounding area plummet and the Secret that is seeking out the Scub Coral to initiate a Scub Burst will disappear, which explains Generation Bleu's goal to collect the Quartz. It is possible, however, to find a damaged Quartz after a Scub Coral outcropping has been destroyed.
In Eureka Seven: AO, Quartz is formed by the Scub Coral to travel to different timelines to escape the Limit of Questions from Eureka Seven. With the Quartz, time and space are the same thing for the Scub Coral. Ten years prior to the series beginning, Eureka was working for the American Forces by removing the Quartz in order to destroy the Scub Coral and protect her son, Ao. However, when a Secret appeared, Eureka merged with the Quartz and attempted to transport it to another universe, but because she wasn't specific enough on where to go, she ended up in limbo between worlds. Ao later joins Generation Bleu in order to find her and takes part in collecting the Quartz. He eventually receives the Quartz Gun, which can be used by collecting a large amount of Quartz.