Does anyone know what this is? (Goldman Sachs Item?)

Hey guys,

I picked this up at a garage sale and cannot find anything close to a lead on what it may be or if its worth anything. Any ideas? The box is made of brass and the inside black felt. You can see what is engraved on the front.

Thanks

It appears to be a securities box. Where some highly valuable documents relating to a bond of some kind were held. Goldman Sachs and co are a global investment banking and securities firm and they seems. Going only on Google stuff a amortizing debenture seems to be something related to selling future shares at current prices (like options). It seems this deal was so good as to have a box made for the paperwork. At $150,000,000 due to be (?) cashed/traded/claimed in 2020 I'd make a special box too.

Please feel free to make up for my lack of understanding of the finer points of futures with something of more substance.