(pics) Physical Bitcoin Bills - For Real World Transactions - Printcoins.com - page 2.

DeathAndTaxes

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Gerald Davis

Quote from: Daily Anarchist on January 04, 2012, 07:31:43 PM

That's really cool! I suppose as you get more confident with what you're doing the markup fee will drop, or disappear altogether. Also, as demand increases, including for larger amounts, there will be bulk pricing for larger notes. But as it's not too likely that somebody is going to order 100 50 BTC notes right now, it's not really that important. I'm glad you have bulk pricing for the 1 BTC notes. It's still a little too high for me right now. But if you can get your prices down to, say, 106 BTC for 100 1 BTC notes, I'd throw down for that.

You're creating a very important product and I'm glad you're putting a lot of thought into it. This can be something that is truly badass and puts Bitcoin on the map for a much larger segment of society.

Why would markup disappear completely?

As far as 0.06 BTC markup. You are aware there is no central bank which can subsidize printing costs. Things like material, labor, custom holograms, etc do time take and resources. Your expectations may be a little unrealistic.

casascius

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The Casascius 1oz 10BTC Silver Round (w/ Gold B)

Quote from: PrintCoins on January 04, 2012, 07:20:25 PM

I brought the price down significantly for the 50 BTC bill, but I do still include a percentage in my markup. I consider it a handling fee for the risk of managing $250 worth of cash. You may think that is no big deal as a transaction is a transaction, but I get a little nervous when I have to handle that much for someone. If someone ordered a hundred 50BTC bills, I would probably need to take the day off from work just to make sure I was ultra careful with each one being loaded.

Maybe we should share some notes on how to efficiently fund bills.

For me, loading BTC on coins gives me virtually no anxiety, even if I'm doing 2000+ BTC in a single run. I have a rock solid way to track and load them. I am using a database to track their loading status, and everything is crosschecked against the master list of bitcoin addresses so I don't load the wrong thing. Also since I keep my BTC on paper wallets, I only unpaperize the BTC I am about to load right then and there - so there's no risk that I send all my BTC to the wrong place by fat fingering an amount.

Daily Anarchist

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That's really cool! I suppose as you get more confident with what you're doing the markup fee will drop, or disappear altogether. Also, as demand increases, including for larger amounts, there will be bulk pricing for larger notes. But as it's not too likely that somebody is going to order 100 50 BTC notes right now, it's not really that important. I'm glad you have bulk pricing for the 1 BTC notes. It's still a little too high for me right now. But if you can get your prices down to, say, 106 BTC for 100 1 BTC notes, I'd throw down for that.

You're creating a very important product and I'm glad you're putting a lot of thought into it. This can be something that is truly badass and puts Bitcoin on the map for a much larger segment of society.

PrintCoins

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Quote from: Daily Anarchist on January 04, 2012, 06:58:13 PM

Whoops, I spoke to soon. Your 50 BTC note is still 3 BTC over spot. If you can make a single 1 BTC note and profitably sell it at 1.30 BTC, then you should be able to make a single 50 BTC note and profitably sell it at 50.30 BTC.

I would imagine the pricing system looks something like this:

Purchasing 1 Note Purchasing 5 Notes Purchasing 20 Notes Purchasing 100 Notes Purchasing 1,000 Notes

1 BTC Note 1.30 BTC 6.25 BTC 24 BTC 115 BTC 1,100 BTC

5 BTC Note 5.30 BTC 26.25 BTC 104 BTC 515 BTC 5100 BTC

10 BTC Note 10.30 BTC 51.25 BTC 204 BTC 1015 BTC 10,100 BTC

20 BTC Note 20.30 BTC 101.25 BTC 404 BTC 2015 BTC 20,100 BTC

50 BTC Note 50.30 BTC 251.25 BTC 1004 BTC 5015 BTC 50,100 BTC

Make sense?

I brought the price down significantly for the 50 BTC bill, but I do still include a percentage in my markup. I consider it a handling fee for the risk of managing $250 worth of cash. You may think that is no big deal as a transaction is a transaction, but I get a little nervous when I have to handle that much for someone. If someone ordered a hundred 50BTC bills, I would probably need to take the day off from work just to make sure I was ultra careful with each one being loaded.

If the markup is a big deal, just buy the open denomination bill, which is the cheapest one available. You can load it with whatever you like, and I don't have to handle your money for you.

Also, note that I just added "a stack of 100 1BTC bills" to the shopping system. There is a nice discount there, and coincidentally it is priced about the same as what you expected in your chart.

Daily Anarchist

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Quote from: Daily Anarchist on January 04, 2012, 06:58:13 PM

Whoops, I spoke to soon. Your 50 BTC note is still 3 BTC over spot. If you can make a single 1 BTC note and profitably sell it at 1.30 BTC, then you should be able to make a single 50 BTC note and profitably sell it at 50.30 BTC.

I would imagine the pricing system looks something like this:

Purchasing 1 Note Purchasing 5 Notes Purchasing 20 Notes Purchasing 100 Notes Purchasing 1,000 Notes

1 BTC Note 1.30 BTC 6.25 BTC 24 BTC 115 BTC 1,100 BTC

5 BTC Note 5.30 BTC 26.25 BTC 104 BTC 515 BTC 5100 BTC

10 BTC Note 10.30 BTC 51.25 BTC 204 BTC 1015 BTC 10,100 BTC

20 BTC Note 20.30 BTC 101.25 BTC 404 BTC 2015 BTC 20,100 BTC

50 BTC Note 50.30 BTC 251.25 BTC 1004 BTC 5015 BTC 50,100 BTC

Make sense?

The question you have to ask yourself is, even at very large orders, what is the absolute CHEAPEST I can sell 1 note worth. If the absolute cheapest amount you can sell a note for is 30 Bit cents over spot, then you'll have to make THAT your target goal for the bulk pricing. Notice above how I made it so that at 1000 notes ordered, the cost per note is 10 Bit cents over spot. Simply adjust that to be 30 Bit cents over spot, and re-adjust the rest to be slightly higher. In that case if somebody one orders, say, 1 note all by itself the cost might be 55 Bit cents above spot. Make sense?

casascius

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The Casascius 1oz 10BTC Silver Round (w/ Gold B)

Quote from: PrintCoins on January 04, 2012, 06:57:30 PM

The downside: this will cost more in labor, shipping and materials.

The upside is that people who don't want to screw around with software will have a reliable way to get a very secure savings wallet, possibly the most secure wallet available to a non-technical person. If we're jamming three or four holograms on this thing, the material costs are already somewhat expensive anyway.

Daily Anarchist

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Whoops, I spoke to soon. Your 50 BTC note is still 3 BTC over spot. If you can make a single 1 BTC note and profitably sell it at 1.30 BTC, then you should be able to make a single 50 BTC note and profitably sell it at 50.30 BTC.

I would imagine the pricing system looks something like this:

Purchasing 1 Note Purchasing 5 Notes Purchasing 20 Notes Purchasing 100 Notes Purchasing 1,000 Notes

1 BTC Note 1.30 BTC 6.25 BTC 24 BTC 115 BTC 1,100 BTC

5 BTC Note 5.30 BTC 26.25 BTC 104 BTC 515 BTC 5100 BTC

10 BTC Note 10.30 BTC 51.25 BTC 204 BTC 1015 BTC 10,100 BTC

20 BTC Note 20.30 BTC 101.25 BTC 404 BTC 2015 BTC 20,100 BTC

50 BTC Note 50.30 BTC 251.25 BTC 1004 BTC 5015 BTC 50,100 BTC

Make sense?

PrintCoins

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Quote from: casascius on January 04, 2012, 06:45:08 PM

Quote from: PrintCoins on January 04, 2012, 06:41:28 PM

I hate to gum up the works, but there is one flaw. If I ever can see the full printed bill in circulation, and I was an evil person who actually was saving private keys, since the second one is in the clear, I would have both, and thus would be back in the beginning again (except with a new layer of trust in the bills).

How I could be evil, is buy these under a false name, have Mike ship them, and then somehow pass them off again to someone else to resell them or spend them.

Yep, it is far fetched, but I predict that in the next two years their will be a boatload of people printing all sorts of bitcoin bills, and this little run-around might become feasible.

Since Mike and I are the only game in town at the moment, and it would be absurd to go through all these steps where I could achieve the same ends without any steps, it should be just fine to use the clear second half of the private key. I would just recommend that when this becomes a common practice, both private keys need to be obscured.

That's possible yeah, but when I get some holograms that are cut as rectangles, then I can deal with that. For now people are going to have to just trust you're not doing that, the same way they probably already trust we're not doing it now. That's why I'm looking to get them to quote us on a continuous hologram pattern that works as both circles and big rectangles, so we can get both kinds out of the same hologram order. My one inch circles are really only good for obscuring a small dot with tiny print like I do on my coins, just no way I could see it covering a full QR code.

Yeah, right now there is a lot based on trust, and I think that even with an un-obscured second key, it works extremely well, since it would take a massive effort on my part to undermine this system.

Since this is paving the way for the future currency producers, I just wanted to show how it isn't 100% of a perfect system. Even as a two part obscured private key, it isn't 100%, as collusion is possible.

Each person added to the scheme increases the trust factor by an exponent as the greater the number of people, the more difficult a conspiracy is (ignoring the possibility of sock-puppets).

The downside: this will cost more in labor, shipping and materials.

casascius

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The Casascius 1oz 10BTC Silver Round (w/ Gold B)

Quote from: PrintCoins on January 04, 2012, 06:41:28 PM

I hate to gum up the works, but there is one flaw. If I ever can see the full printed bill in circulation, and I was an evil person who actually was saving private keys, since the second one is in the clear, I would have both, and thus would be back in the beginning again (except with a new layer of trust in the bills).

How I could be evil, is buy these under a false name, have Mike ship them, and then somehow pass them off again to someone else to resell them or spend them.

Yep, it is far fetched, but I predict that in the next two years their will be a boatload of people printing all sorts of bitcoin bills, and this little run-around might become feasible.

Since Mike and I are the only game in town at the moment, and it would be absurd to go through all these steps where I could achieve the same ends without any steps, it should be just fine to use the clear second half of the private key. I would just recommend that when this becomes a common practice, both private keys need to be obscured.

That's possible yeah, but when I get some holograms that are cut as rectangles, then I can deal with that. For now people are going to have to just trust you're not doing that, the same way they probably already trust we're not doing it now. That's why I'm looking to get them to quote us on a continuous hologram pattern that works as both circles and big rectangles, so we can get both kinds out of the same hologram order. My one inch circles are really only good for obscuring a small dot with tiny print like I do on my coins, just no way I could see it covering a full QR code.

PrintCoins

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Quote from: BurtW on January 04, 2012, 06:18:45 PM

Mike, do not answer this yet. Let me edit it with the "crossing system" you proposed...

Quote

Person 1:
  Create a random private key (a)
  From the random private key calculate the standard public key (A = a*G)
  Print the private key (a) on the bill and cover it with a sticker
  Send the bill, along with the corresponding public key (A), to person 2

Quote

Person 2:
  Create a second private key (b)
  From the random private key (b) and the public key created by person 1 (A) calculate the final public key (B = b*A)
   [Note b*A = b*a*G which makes the final private key b*a]
  Print the private key (b) on the bill - As you said this could be left in the clear if you want to
  Calculate the public key address of public key B and print it on the bill
  Fund the public key address with the correct number of BTC

I hate to gum up the works, but there is one flaw. If I ever can see the full printed bill in circulation, and I was an evil person who actually was saving private keys, since the second one is in the clear, I would have both, and thus would be back in the beginning again (except with a new layer of trust in the bills).

How I could be evil, is buy these under a false name, have Mike ship them, and then somehow pass them off again to someone else to resell them or spend them.

Yep, it is far fetched, but I predict that in the next two years their will be a boatload of people printing all sorts of bitcoin bills, and this little run-around might become feasible.

Since Mike and I are the only game in town at the moment, and it would be absurd to go through all these steps where I could achieve the same ends without any steps, it should be just fine to use the clear second half of the private key. I would just recommend that when this becomes a common practice, both private keys need to be obscured.

Daily Anarchist

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Quote from: PrintCoins on January 04, 2012, 06:27:15 PM

Quote from: Daily Anarchist on January 04, 2012, 05:56:14 PM

I think you're making great progress on this and I am eagerly awaiting the day that I can feel confident in purchasing your Bitbills. There are several more things that need to happen for them to be a truly kick-ass Bitcoin-backed paper currency.

Right now your prices are prohibitive.

I see that you are charging less premium(percentage wise) on a 50 BTC note than a 1 BTC note. But that doesn't really make sense. I'm assuming that the cost of making the 50 BTC note is ~ the same as making a 1 BTC note. Therefore, when an individual purchases a single solitary note, whether it be a 50 or a 1, the premium(in nominal terms, not percentage of note value) should be the same.

The savings should come in when an individual purchases large quantities of the same note. This would be bulk pricing. And since people are much more likely to buy 1's in bulk than they are 50's in bulk, we can reasonably expect people to get better discounts on their 1's than on their 50's, which I think is the goal you were trying to achieve when pricing the notes in the first place.

You are right on. I adjusted my formula based upon your post, and the price of the higher denomination bills includes a much smaller markup than before.

Glad to help. Keep up the good work!

PrintCoins

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Quote from: Daily Anarchist on January 04, 2012, 05:56:14 PM

I think you're making great progress on this and I am eagerly awaiting the day that I can feel confident in purchasing your Bitbills. There are several more things that need to happen for them to be a truly kick-ass Bitcoin-backed paper currency.

Right now your prices are prohibitive.

I see that you are charging less premium(percentage wise) on a 50 BTC note than a 1 BTC note. But that doesn't really make sense. I'm assuming that the cost of making the 50 BTC note is ~ the same as making a 1 BTC note. Therefore, when an individual purchases a single solitary note, whether it be a 50 or a 1, the premium(in nominal terms, not percentage of note value) should be the same.

The savings should come in when an individual purchases large quantities of the same note. This would be bulk pricing. And since people are much more likely to buy 1's in bulk than they are 50's in bulk, we can reasonably expect people to get better discounts on their 1's than on their 50's, which I think is the goal you were trying to achieve when pricing the notes in the first place.

You are right on. I adjusted my formula based upon your post, and the price of the higher denomination bills includes a much smaller markup than before.

BurtW

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All paid signature campaigns should be banned.

Is this the proposal? Should work.

Quote

Person 1:
Create a random private key (a)
From the random private key calculate the standard public key (A = a*G)
Send the public key (A) to person 2

Quote

Person 2:
Create a random private key (b)
From the random private key calculate the standard public key (B = b*G)
Send the public key (B) to person 1

Quote

Person 1:
From the random private key (a) and the public key created by person 2 (B) calculate the final public key (F = a*B)
[Note a*B = a*b*G which makes the final private key a*b]
Calculate the final public key address of the final public key (F)

Quote

Person 2:
  From the random private key (b) and the public key created by person 1 (A) calculate the final public key (F = b*A)
   [Note b*A = b*a*G which makes the final private key b*a]
  Print the private key (b) on the bill - and cover it with a sticker to hide it
  Calculate the public key address of public key F and print it on the bill
Send the bill to person 1

Quote

Person 1
Finally print the private key (a) on the bill
Can match the public key address calcluated above with the public key address on the bill

Daily Anarchist

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With the increase purchasing power of Bitcoin seemingly inevitable, could we see the day where Printcoins has bills ranging as low as 1 BTC to as high as 100 BTC much like FRN's and Cas has coins ranging from 0.01 BTC to 0.50 BTC much like today's FRN coins? That would be badass.

casascius

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The Casascius 1oz 10BTC Silver Round (w/ Gold B)

Quote from: Red Emerald on January 04, 2012, 05:58:48 PM

This sounds awesome. There should also be a utility for taking the two private keys and combining them into a wallet import format of some kind so people can easily use these bills.

I intend to promote using private keys with the prefix "6" instead of "5" to mean keys that require other keys to be combined. To get the "6", I intend to use 0xA2 instead of 0x80 as the version byte. That way, a UI allowing redemption will know that this is only half of a private key, so it will know to ask for the other half.

As it turns out, 0xA2 thru 0xA9 also produce prefixes of "6", so for example 0xA3 could be used to signal a key in three parts, if somebody finds a use case for it.

Red Emerald

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Quote from: casascius on January 04, 2012, 05:53:05 PM

Probably what I should do is make a derivative program of Casascius Bitcoin Address Utility that does both sides of the work, and then open source it. Function one would generate a privkey/pubkey file (csv), function two would take the local privkey file and a foreign pubkey file and generate a bitcoin address list, which we would both independently sign and publish.

This sounds awesome. There should also be a utility for taking the two private keys and combining them into a wallet import format of some kind so people can easily use these bills.

Daily Anarchist

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I think you're making great progress on this and I am eagerly awaiting the day that I can feel confident in purchasing your Bitbills. There are several more things that need to happen for them to be a truly kick-ass Bitcoin-backed paper currency.

Right now your prices are prohibitive.

I see that you are charging less premium(percentage wise) on a 50 BTC note than a 1 BTC note. But that doesn't really make sense. I'm assuming that the cost of making the 50 BTC note is ~ the same as making a 1 BTC note. Therefore, when an individual purchases a single solitary note, whether it be a 50 or a 1, the premium(in nominal terms, not percentage of note value) should be the same.

The savings should come in when an individual purchases large quantities of the same note. This would be bulk pricing. And since people are much more likely to buy 1's in bulk than they are 50's in bulk, we can reasonably expect people to get better discounts on their 1's than on their 50's, which I think is the goal you were trying to achieve when pricing the notes in the first place.

casascius

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The Casascius 1oz 10BTC Silver Round (w/ Gold B)

Yes, we'd use point multiplication.

Each of us has a private key, so we should have no problem computing the addresses if we trade public keys.

If we both trade public keys, then Rob can pre-print the complete bitcoin address, and I can also print it a second time in small print for confirmation that the two still correspond. My hologram isn't big enough to cover the whole QR code without actually sticking to it, so I'd print my QR code in the open, and stick my (windowed) hologram beside it, such that the firstbits of the combined address (as I printed it) show through the window.

Probably what I should do is make a derivative program of Casascius Bitcoin Address Utility that does both sides of the work, and then open source it. Function one would generate a privkey/pubkey file (csv), function two would take the local privkey file and a foreign pubkey file and generate a bitcoin address list, which we would both independently sign and publish.

BurtW

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Quote from: casascius on January 04, 2012, 03:34:15 PM

Example: You and I both generate a large batch of keypairs. We exchange public keys and compute the bitcoin address of the resulting set. You make your bills and send them to me in completed sheets where I can feed them through an inkjet printer. I print a 2nd key and QR on them (doesn't even have to be covered up). I put a "zero BTC" hologram on it as my stamp of approval, and then I ship it out to whoever you tell me to. (I already have the holograms - I had like 4000 of them made that say "zero BTC", not sure in advance what I'd do with them, but this might be perfect)

Mike, There are a few details missing here.

First question: are you proposing that you guys use the point addition method or the serial point generation method that we recently discussed in the other thread?

I was assuming everyone was moving to using the serial point generation system (private key multiplication)

I think in order to make it as simple as possible for the customer you should end up with the bill having just three numbers/QR codes:

The final public key address
The first private key (under a sticker)
The second private key (under a sticker)

I think it might be ok to leave off the second sticker but the first one is critical and adding the second sticker to cover the second private key would avoid confusion and cover up another number/QR code so the customer only sees the one public key address/QR they need in order to fund the check or check the value of the preloaded bill.

PrintCoins

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Quote from: casascius on January 04, 2012, 03:34:15 PM

Rob, we should do a deal where one of us manufactures the bill, sends it to the other, and we each add a private key.

Example: You and I both generate a large batch of keypairs. We exchange public keys and compute the bitcoin address of the resulting set. You make your bills and send them to me in completed sheets where I can feed them through an inkjet printer. I print a 2nd key and QR on them (doesn't even have to be covered up). I put a "zero BTC" hologram on it as my stamp of approval, and then I ship it out to whoever you tell me to. (I already have the holograms - I had like 4000 of them made that say "zero BTC", not sure in advance what I'd do with them, but this might be perfect)

That would work.

Code:

Bill Example
--------------------------------
5 Bitcoins 5

Priv1 Pub1
Pub Combined
Priv2 Pub2

5 5BTC
---------------------------------

I can accompany the sheets with a text file of public addresses so you don't need to get them directly from the sheets.

Do you have code (in any language) on github somewhere for merging the private keys? If I can also have some example outputs that I can test against, I can see if I can port it over to javascript and make a simple web app for users.

Topic: (pics) Physical Bitcoin Bills - For Real World Transactions - Printcoins.com - page 2. (Read 8835 times)