Be careful, if one thinks about it, “yes” your Eagles are legal tender, but look at the amount of tender:
1 Dollar.
If the Gov ordered all us mint coins turned in for replacement by plastic slugs, if they paid you 1 “Dollar” in plastic slugs, then your metals would not have been “confiscated”.
That was what FDR’s goons did back in the 30’s, Gold was price controlled, he devalued Gold down to 19 dollars an OZ, confiscated it, then raised the price to 32 dollars an OZ.
Actually they are 50.00 but I will accept no less than 1600.00 worth of goods.