1979 Cent Double Date

Yes, it's listed as double date in trends.
That is called Die Deterioration Doubling.
Die Deterioration adds to the numbers while one form of Machine Doubling cuts into the numbers.
I have about 80 or so from this year. I could post some images of each type if needed.

Not trying to , just trying to understand.

Can't figure out why Machine Doubling and/or Die Deterioration would be something desirable enough to list as a premium collectable.

Why wouldn't deterioration affect more of the die than just the bottom of the date?

It still looks like Machine Doubling to me, but I always thought that MD was random, random, random. And apparently, there are enough coins with this error consistent enough to list, so maybe deterioration is the answer.

castor, thanks for the links, but I can barely read English, much less French. (Yes, I saw the translate button on the first one.)

That's what I can't get my head around. If it were a variety it would be minted on EVERY SINGLE coin the same way. The variety would be on the dies themselves.

I would agree that it is an error, but not a variety. But, a collectable error? We have machine doubled and die deteriorated coins left and right here in the US.

Is it because of your QC that makes this desirable? Maybe the mintage is limited to a particular die state before they get pulled?

I'm just trying to understand the premium on what (down here) is considered the normal life cycle of a die.

These are good questions, I'll try to answer them well.

The 1979 double date is an error and loosely given the term 'variety'. It is listed as having a premium because of its popularity and appeal. I, my self can find them easily and see the CCN premium being high.

I had read that these errors come from different working dies and increased as the striking proceeded. With that knowledge I tracked and mapped 13 different examples from 2 or more working dies. If I take into account die clashes and Obv. doubling, I get 38+ varieties of this error. Some of these are easier to find than others.
I even have one that has both mechanical and deterioration doubling on the reverse.

Die Deterioration Doubling is uncommon on Canadian cents, 1967 is another example.
This doubling is clean and even on cents but becomes jagged and clumpy when you find it on larger denominations. The examples of American cents I've seen resemble our higher denominations.

Its simply a different game here in Canada. Since doubling on cents is ignored and unexplored the prices are inaccurate and sometimes inflated.

Scooby: You're right in a more general sense that a few of our interesting Canadian varieties are not true "varieties", but rather "consistent errors". I'm thinking of the 62 double date nickel, the attached leaf 1947 dimes, the 64 extra water line nickel (a simple die crack), and certainly the 79 double date cent here.

Let me add to what was already said.

As a collector, I am interested (to a small extent) in these "consistent errors" because (1) they are often common enough to be "found" for face value or bullion value, yet not so common as to be completely standard and (2) we lack a lot of the typical varieties in 20th century Canadian coinage. (I get bored after completing the modern date sets in other words!)

Finally, I don't see a huge difference between collecting a variety and a mass-produced error. It's not as though the US mint truly intended all XYZ million of the different 1960-D RPMs. By the same token that die-cracked 1964 Canadian nickel might have been used after the crack was "known" to the mint worker!

Having said all this, I'm totally with you on the 1922 no D and 3-legged Buffalos. They, along with certain of our varieties north of the border, are simply hyped by dealers. (But the 1979 doubled cent is an innocent hype if it is a hype at all -- it's so cheap.)