Hi Tapeslack,
Firstly, I’m sorry to hear this issue occurred for you in your game.
From reports we’ve had from other players it appears that checking the cartographer before returning to your save may be related to this occurring on consoles. This matching up with what you described and I add this info to my report for the team.
While I do not know the details of the issue from the console team’s side, I am gathering what info and workarounds I can in the following post for players - [Known Issue] Rafts/Gyro vanishing after sleep/save - I completely understand how frustrating this issue can be, especially for players such as yourself that lose a lot of materials when it happens.
We value all feedback (good and bad) for the game but ask that when reporting issues that you please adhere to the rules of the forums - Rules and Guidelines - Stranded Deep - when commenting and avoid insulting staff members.
To prevent further posting in an older thread, I have also moved your post to it’s own thread in the bug reports section.