Shipping jewelry/gems from Canada to U.S.

[the_mother_thing]

Wasn't sure where to pose this question - when shipping loose gems and/or gems mounted in a setting, are there any fees/import taxes/etc for the recipient to be aware of, and if so, is there a difference if the jewelry and/or gems are purchased from a dealer or private sale? Any issues/considerations with insuring the aforementioned items for shipping?

Thanks much in advance for any information/experiences you might share.