Rangemaster,
Now that you mentioned it I do remember our next-door neighbor (in 1951 or 1952) bringing over a Jap grenade bring-back for my dad and me to look at. I was probably ten or eleven at the time but I was impressed by that thing. The three of us broke it down (no bright people in attendance, apparently) and just ended up with a whole bunch of concentric wooden rings with a wooden handle, lanyard attached.
The next morning it was gone so I have to assume that the neighbor and my dad got it back together again.
That vial of black sand is a treasure as are the maps and picture!
I hope you find time to post pics of them here...
Anything that a relative brought back is a treasure to protect.
Phil