Amber burns. The amber from the amber room probably burned in 1945.
Sadly, yes...the most recent research (conducted after the Iron Curtain fell and Soviet files became available) indicates that the Amber Room was likely lost in the blaze that destroyed Konigsberg Castle in the spring of 1945. The Soviet officer assigned to find it as part of the Red Army initially made that conclusion in a report, then was forced to recant it.
Fortunately, it has since been reconstructed from photos and other old documentation of the original.