chowB

Depends la, if you wanna keep them: better ask the shops to write a receipt for you, they're happy to write lower price if you like (in case you wanna sell them). Then the canada custom will have a greater chance to tax you base on the receipt, if they think it's reasonable. But if they think it's not reasonable, they may still tax you base on their own judgment ga wor.
Or if you don't care to keep them but cash, you better don't bring in "cash" cuz too much cash could be considered to be "black money". You better do electronic transfer from a bank in HK to Van, much safer la.

chowB

I won't risk to do any smuggling like action lor. I wonder if it is possible to ask and pay for a certain fee to any of the "gold shop" in HK, ask them to write an estimation for how much your jewelery worth on a formal document (at a lower price if possible, of course la). Then bring everything to canada with honest declaration to custom, say they're all wedding gifts from your families, hope they'll let you go or at least to tax you base on your document la.