They can be created, but they also seem to be left behind in certain cases of gathering or highly dense Seithr. It serves as a small sample fragment of the Boundary’s power. It doesn’t use souls as a conduit of its creation making them a simple resource to design, and it is said to be a very basic stage of concentrated Seithr.
Boundary Fragments, like the Seithr Core, were versatile tools to mankind during the Third War and prior. They serve for various purposes. Their energy isn't sufficient enough to give its user any enhanced abilities from the Boundary however, but can have effect on emotion and the mind.
Blue Boundary Fragments appear to be a part of certain weapons and Azure Interface Primefield. But interestingly, also have been seen in people, giving the idea they can be implanted.
Red Boundary Fragments are an oddity, they’re found lodged inside of the Seithr Being's body. The spot of its implantation varying anywhere on their form. Little is known about why a Boundary Fragment turns crimson. Red shards do seem to have a completely negative effect on the mind, as seen by Nex's experiences.
In form, the Boundary Fragment is typically no bigger than a 2-3 inches, though some have been seen to be larger. It's crystallized energies that are in the shape of a translucent diamond and within its body is colored auras of varying greens and blues, while crimson shards are either black or red.