Author Topic: New Book!Chinese modern gold and silver coins buyer's guide.With reall mintage!  (Read 33978 times)

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Offline comeaux

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I'm also a collector. :) I believe that it will be difficult to get an accurate mintage figure for modern Chinese coins because the mint did not keep track of it in the earlier days from what I remember. If the mint does not have an accurate accounting of mintage figures, what's the guarantee that a third party will know the correct numbers? This is why I personally only use mintage figures as a guide, but I also observe the market and see which coins are readily available and which are seldomly seen. Since I'm a collector as I mentioned earlier, I buy the coins that look nice in my eyes. That way, I am happy with just owning them. With the panda series, I think that nobody can go wrong with the design for most years. ;)
Totally agree with everything you have said here ... we have a lot in common mrslick  :thumbup1:

Offline mrslick32

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Totally agree with everything you have said here ... we have a lot in common mrslick  :thumbup1:

Does this include being good looking? Lol! ;)

low

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Can you check whether the 1994 BU 1 OZ GOLD is correct. Less than 1100, even rarer then the bi metal version of 1994

From another of Mr. Ge's book, with pricing.

Actual mintage 10703. "3" was omitted in the new book.

All the 1990 proof gold panda has planned mintage 8000 and actual mintage 5000.

Offline badon

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Honorable Badon-
I don't like to keep bringing this up, but your inaccuracies must be corrected. Your quote of 14.7psi at seal level is for normal atmostpheric pressure, not vacuum (subatmostpheric) pressure. So even without any vacuum involvement, per your calculations, our fragile TPG slabs should surely be exploding at this very instant. But I have one in front of me...and it's not. Also, you state yourself that pressure is a measure of force per unit area. You can calculate the total force all you want; it is certainly a worthy arithmetic problem. However, confusing total force and pressure is not allowed. In this universe, pressure is the important variable, not total force. The physical vacuum (subatmospheric) pressure involved in sealing a slab would have no crushing effect whatsoever; even if the slab was sealed hermetically, the force exerted would actually be one of expansion (or 'negative pressure,' as much as I dislike that term); but they're not hermetically sealed, so this is a moot point-->no pressure gradient equals no work done to slab. The only new source of force or potential energy on the slab would be from the shrinkage of the vacuum seal wrapper. I've never actually checked this myself, but I feel it's a safe bet to assume millimeter thick mylar bags will rip long before the slab will crack. Ultimately, it all comes down to permutations of Ohm's Law. Bottom line: unless you are utilizing a specialized academic laboratory- or industrial-level vacuum sealer, the slabs are safe.

As I think about it, the 'outward' vector forces on the vacuum-sealed slab would actually be ameliorated by the 'inward' vector forces of the shrinking wrap.  The stability and durability of the vacuum-sealed slab would likely be substantially higher than an untreated one. It's possible even a synergistic (and not just additive) effect could be observed. Anyone have a vacuum sealer and a hammer? I would be happy to volunteer two slabs for a test.

Yes, you are mostly right in your thinking about the balance between inward and outward pressure. However, that only applies to fully balanced forces. Since a slab has projections (ridges, etc), the plastic of the vacuum sealer stretches out over those projections, leaving areas that do not have balanced forces. There will be areas of the slab that will be loaded with much larger forces than my simple calculations demonstrate, just like the supports of a tent are loaded more than the fabric of the tent itself.

Total force and pressure can be the same things, depending on how you calculate "total force". Pressure has no meaning without area. You may have meant "net force". Since the inside and outside of the slab do not have the same pressure, the plastic faces are loaded with force according to the calculations. But, since the pressure inside is not zero, my calculations may not be accurate. But that does not mean my calculations are too high, it only means they're not a complete model of all the forces on the slab.

When you account for projections, the forces might be higher than my calculations indicate. More advanced mathematical modeling would be required to produce more accurate numbers (FEA). Also remember that there is no such thing as negative pressure in normal physics - there is in advanced and theoretical physics, but it's not relevant in this circumstance.

In short, the only thing we can be certain of is that there are forces on the slabs. These forces could be quite high, depending on the interacting geometry of the plastic vacuum sealer sheeting, and the slab. It also happens to be that the sonic sealing on the slab is a variable that can't be accounted for. So, it may not actually be possible to calculate whether the vacuum sealer puts enough force on the slab to exceed the yield strength of the sonic seal.

My solution? Don't bother calculating any of it - the risk is unnecessary, the reward is close to zero, so just use normal plastic bags (with balanced internal and external pressure) instead of a vacuum sealer. No need for calculations, and all forces are balanced, so the net force caused by the bag will be zero. And you still get a seal.

Unless you plan to drill a hole in the slab and suck the air out, a vacuum sealer won't help, but could hurt.

Offline badon

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Can anyone answer this legal question:
Can a single individual own copyright privileges to the actual mintage figures for an entire country when those coins are pubically released and considered a denominated means of exchange?

I know some people have possibly justifiable reasons for not posting mintage figures but I am curious to know the legality of the situation given the monetized nature of the items.
 :(

Discussion of copyrighted, published mintage figures usually will fall under fair use protections, so long as you're NOT republishing a substantial portion of the copyrighted work. Since "fair use" is open to interpretation, I recommend not repeating the specific numbers if you want to be on the safe side.

But, there's a more important reason: We want to support the authors who did the work in producing these numbers for us. By buying the books, and encouraging others to buy the books also, not only do you have more to talk about, but you also ensure that these authors are rewarded for their work, and will continue to produce more work for us.

Just because you can legally do something, doesn't mean you should. But, after a book has been out for a year or so, it becomes safer to discuss the information in the book under "fair use" provisions, without damaging the earnings of the author. We'll see how it goes, and fortunately, the authors are available to us so we can ask them what they think about it.

On the upside, talking about the books helps to sell them, so let's not panic too quickly before we give some careful thought to whether talking about specific figures in the books is the right thing to do or not.

Offline SANDAC

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Got the signed book this afternoon!  I love the way the book is organized by year.  That wouldn't have worked for the imperial/republic era, but it is definitely the way to go for the modern coinage.  Lots of new information to absorb, and I need to read up more on Mr Ge's stars designation.
I completely agree with supporting authors who did these fine works for us.  While Fair Use grants individual to discuss few specific items in a book (which does contribute to greater circulation of a book), I felt the editor/moderator of a forum where such discussion are concentrated may need to apply a more restrictive interpretion of Fair Use so not to give away the "meat" of a book.  BTW, you moderators are doing a great job here. 

Grigoryan Coins Ltd

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happy to know that many CCF members already got books. i still have few left.

Grigoryan Coins Ltd

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this book is big weapon! includes all prices for all coins from 1979 - 2011 , also includes information about: size, real mintage, price for sets.Must have every collector and buyer!

Offline badon

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I just received my copy from Shanghai Coins, and it's easier to follow than I thought it would be, even though most of it is written in Chinese.

Offline DiggingNorway

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niced book, thanks shanghaicoins!

Offline PandaOrLunar

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So there are 2 editions (2010 and 2011) already?

« Last Edit: December 03, 2011, 11:26:24 AM by PandaOrLunar »

Offline Obsidian

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No, those photos show the book and the separate price guide.

Offline PandaOrLunar

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The separate price guide come with the book or is it a separate purchase?

Offline Panda Halves

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Separate purchase. In my opinion the price guide is a must have. I actually really like this book set in general and find them quite nice and useful. They are so cheap that they are a great value. Much nicer than that big red book and cheaper too.
I like them.

PH

Offline dobedo

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this book is big weapon! includes all prices for all coins from 1979 - 2011 , also includes information about: size, real mintage, price for sets.Must have every collector and buyer!
Shanghai Coins, How much is this 2nd book? How is it different from the Pricepedia on Panda coin prices? Thanks.