Inertium

Inertium was a type of ore.

Kasidy Yates Interstellar Freights shipped inertium. In 2371, her conversation with Benjamin Sisko in Deep Space 9's cargo bay was interrupted by a loud crash, which she believed to be the inertium ore. After she told Sisko that she had to see to it, he offered to help her, but she told him she could do it herself.