In episode VII,
When Kylo Ren is interrogating Rey, he removes his helmet and places it in what looks like a tray of dirt or ash, similar to the platform that holds Darth Vader's helmet.
Assuming the platform is similar to the one that held Vader's destroyed helmet, then it could possibly symbolize
how Kylo Ren tries to emulate Darth Vader. Placing his helmet on a similar "altar" could be a statement of power. This might be another reason why he was greatly disturbed when Rey spoke his fear of failing to become as powerful as Darth Vader.
My question is, what does the platform, or his placing of the helmet on the platform, mean?
It could have a literal, practical interpretation, or a symbolic explanation.