Literally. Technology available since about 250BC to be precise.
Background. Sent a parcel to Canada containing figures. Put the correct code on the customs declaration and described it as 'metal castings, Tin/lead alloy' Simple.
It got stuck for a few weeks in the Langley centre where stuff is processed before going abroad. Eventually they sent the parcel back to me as possibly containing prohibited material. Found the following letter in the returned parcel:
In other words, the reason they returned it was because they DON'T HAVE THE TECHNOLOGY to measure the density and determine the composition when the label clearly say tin/lead alloy!!! A problem solved by Archimedes in 250BC!!!