Given silver bouillon and would like to cash it out and somehow add it into TSP. Any ideas?

Other than the obvious choice of increasing my contributions from my paycheck to max out yearly contributions for the next few years and living off the cash from the silver (don’t want to waste the silver’s cash on diapers, food, gas, etc) any other ideas of how one could theoretically cash out some silver bouillon and add that into their TSP account? Currently sitting on about $40K in silver but with potential 16 years+ in TSP, that same 40k is more like $120k+.

Would opening another traditional or Roth account somehow then in the future merging them together work?