Sorry Sandro but the survival of materials is out of whack. When our ship is destroyed, the premise is that we are ejected in a Remlock suit and 'transported' to the last station we'd docked at, is it not? The fact that happens instantly is an artificiality for gameplay reasons, sure, but there's the reason our cargo doesn't survive for example. Now, if materials are a tangible object like cargo, nor should they survive ship destruction - it makes absolutely no sense for it to survive. Survival of an intangible such as exploration data or bounty vouchers is another matter (data is something that should logically be survivable if stored correctly, such as data storage integral to the Remlock suit), but 'physical' items like cargo and materials should not survive ship destruction any more than ship modules etc do, end of story (apart from the possibility of them surviving for an attacker to collect - they shouldn't magically respawn with the CMDR).
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The logical approach would have been to have the ability to rent or purchase warehouse space or something similar on a station and use that to store quantities of materials for later use. That would require players to judiciously decide how much risk to take with materials (ie when is the right time to return 'home' to place some into storage vs the risk of losing all you have onboard). Anything tangible onboard your ship should be at risk, just like cargo and the rest of the ship equipment. Survivable materials held onboard is just plain dumb. I strongly recommend Frontier rethink the mechanisms required for survival/storage of materials.