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Please explain what you see as an error. All I see is a well circulated 1987 Loonie.
Also always show both sides of the coin when posting. You have 5 of the reverse
and none of the obverse.

That is known as a broken post. Not really an error, it is part of the minting process.
Quite common on D and P mintmarks and adds no value.
Nice photography and cropping, just what we need when evaluating coins.

It’s damage.
There is no way that could have happened when it was struck.
Maybe someone was trying to drill a hole in it.

Hard to tell whether it is a crack or a die chip but it doesn’t make much difference.

Hard to say from the photos supplied but it does not matter as the “No Chrome” variety
is no longer recognized by the graders as the chrome can be chemically removed making
it impossible to tell between a original and an altered nickel.

If you are asking for our help, then help us by posting a clear photo of both sides of the coin along with a closeup of your area of concern. Please be explicit in your question. ( Do not say something like “Is this an error” point out what you think is an error.) One coin per posting with date and ...

The mint does not release figures on different varieties.
The number minted would be included in the overall mintage of 2,650,000.

It does.
You have to click on where it says “Mint State” because there
is no extra value to these unless they are uncirculated.

To give a more accurate grade, we need to see a complete clear photo of both sides.
Can’t grade from a partial photo.

Always take a photo of the complete coin so we can get some perspective of the “error”.
Sometimes photos can be too large. Also include the date in your heading, sometimes this can be important.

You only need one, errors are the same in Canada as they are in the US.
Try Amazon
US ERROR COIN GUIDE 2024 COLOR EDITION
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Looks like the patched canoe variety to me. Nice find.
There would be slight differences in some of them as the
chrome plating on the die continued to break away.

ErrorBeauties2233 Then how do you explain two different dates plus the fact that if it was struck twice, the second impression would be raised and reading positive. It is also out of round which means that it could not have happened while in the collar and the reverse has been flattened from the obv...

Condition plays a big part in their value so without pictures I would say anywhere between $10-25.00 each.
Consecutive numbers in modern notes would not have any part in the value.

Not an error, not double struck.
It is what is called a vise coin or a garage job. Another coin has been pressed into it.
If it was double struck, the letters would not be incuse and reading backwards.
Just a damaged cent now.