Ionite
From Wookieepedia, the Star Wars wiki.
Ionite was a very rare and valuable material, only found on Bandomeer. Inherently ionite interfered with energy fields, such as deflector shields, due to its ability to hold neither a positive nor a negative charge, but rather an alternate charge. In the presence of positively charged elements, it carried a negative charge that negated the positive charge, and vice versa. Any electronic device in its proximity was thus voided and ruined.
However it was found in roughly 4,950 BBY that if concentrated correctly, ionite could be refined and made into a compound with varying explosive materials to make ionite weapons. Though never fully exploited by a naval power, what ionite did come into the possession of willing powers could be turned into grenades, bombs, and missiles with the power to completely deplete shields, and render differing opponents completely defenseless. Most ionite was found on Bandomeer.
