Prohibited things which can't be brought to Canada

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If you want to cross the border without issue, it is not just what you should not bring it also is about declaring. 

Only carry prescription medication.  Items like cannabis might be legal in Canada soon but it is illegal to transport cannabis items across the boarder.  This includes candies or seeds.   Even items that you might use during the enjoyment of such items might get you pulled to the side either by a drug sniffing dog or by random inspection so just avoid the headache.

Firearms are a big issue.  In Canada, we are not allowed to carry firearms on our general person.  You must have permits to transport hand guns from your home to a designated location like a firing range.

Raw food whether it is dried or not is likely not something you want to carry and will likely be taken as it might contain invasive organisms.  If you have the banana or apple in your bag for the flight, eat it before you land.  I would also avoid items like cheese.

Animal and animal products are another thing to avoid.  So don't bring the turtle shell or ivory tusk with you.  Leave it with the animal, they will make better use of it.

Tobacco and alcohol, you are allowed a bottle of alcohol and a carton of smokes per adult. 

Cash, you can transport up to $10,000 in cash or equivalent items so, that diamond that you are carrying worth $10K, declare it.  Otherwise it could be confiscated and you are fined for not declaring.

If you for some reason need to bring items greater than you allowance, I am sure there are permits that can be obtained but this needs to happen before you arrive at the airport or boarder.  The boarder officers generally are not going to like surprises.

I understand that you may want to bring items with you to remind you of your home land but you can find most foods and cultural items here in Canada if you go to the any of the major cities.

Hope this helps.