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1  Economy / Collectibles / Re: Potentially interested in selling two loaded 2012 Casascius 1 BTC coins on: May 26, 2017, 11:02:59 PM
Thread is now closed.

Thanks for the interest everyone! A deal is now underway with greenplastic  Smiley

Lesbian Cow, I appreciate the recommendation, thank you.
2  Economy / Services / Re: LEGENDARY ESCROW SERVICE (More than 19K BTC transferred) on: May 26, 2017, 06:38:22 PM
Under what conditions do you generally release the funds back to the buyer?

When the seller asks me to. I'm not a judge or jury. I make no decisions. Any disputes are handled by the community. In ~4 years of providing escrow services, I have never once had to send the funds somewhere that wasn't agreed upon by both parties.

I understand, this makes sense. Thanks for the details!
3  Economy / Collectibles / Re: Potentially interested in selling two loaded 2012 Casascius 1 BTC coins on: May 26, 2017, 06:34:41 PM
Hey all, I've received several great offers from 1.15 to 1.2 each.

Is anyone willing to offer more? Looking through the forum, I don't see too many 2012 Casascius brass singles for sale these days.

Have the coins been cleaned?

They have not been cleaned.

Where are these coins shipping from?

Priority shipping out of the USA.
4  Economy / Services / Re: LEGENDARY ESCROW SERVICE (More than 19K BTC transferred) on: May 26, 2017, 03:53:03 PM
Do you also also escrow the goods themselves, by having me mail them to you once you receive the BTC payment?

Nope.  I have no plans to pretend to be a goods verification expert.  I help transfer BTC from one address to another safely at the request of a buyer looking to spend Bitcoin.

Thanks for the quick response! I understand why you would want to avoid verifying goods Smiley

However  I'm curious what the process is like if the buyer claims an issue with the delivery during the escrow transaction. If the buyer is acting fraudulently, that would be a huge risk for the seller.

Under what conditions do you generally release the funds back to the buyer?
5  Economy / Collectibles / Re: Potentially interested in selling two loaded 2012 Casascius 1 BTC coins on: May 26, 2017, 06:09:57 AM
You are most likely going to get a much better deal selling them verses peeling them and redeeming the BTC value, even if you accept a very lowball offer from someone with a high reputation.

Thanks for the advice! I'll keep this in mind.

What price are you wanting for them, face value and are you willing to ship worldwide?

I'm definitely looking for some sort of premium over the face value of 1 BTC each. I'm curious, why are you posting this from an account that was registered 30 minutes ago?
6  Economy / Collectibles / Potentially interested in selling two loaded 2012 Casascius 1 BTC coins on: May 26, 2017, 05:58:00 AM
UPDATE: Thread is closed, a buyer has been found.

----------------------------------------------------------

I have two 2012 Casascius 1BTC coins that I'm interested in selling. I'm the original owner (I can produce original packaging and e-mails) and the coins are fully loaded, just as I bought them.

I have never sold here before and I'm somewhat skeptical about transacting through a forum, but if I get a good offer and we are able to arrange a low-risk escrow transaction, then I am open to selling. Otherwise I'll just cash them via coinbase  Smiley

I've added pics of the front and back of the two coins. They are in decent condition, but do have a few minor scuffs/scratches.

Let me know if you are interested!

The public addresses are:
1CSPS2xwT2tKuid1gyUfNa5hNiZGkpvuQg
1CS43QFQMdqyLfXrdyhukB9mQakxK6kSAp

Back:


Front:

7  Economy / Services / Re: LEGENDARY ESCROW SERVICE (More than 19K BTC transferred) on: May 26, 2017, 05:26:34 AM
Hello OG Nasty!

How does escrow work with physical goods? Do you also also escrow the goods themselves, by having me mail them to you once you receive the BTC payment? And then you send me the BTC payment (minus your fee) once you've received the goods? I would send the goods to you with a tracking number and delivery confirmation, of course.

If I were to the send the goods to the buyer directly, it seems to me that would open up a lot of possibilities for complications, as they could claim the goods never came, etc.

I am considering selling a few untampered physical Casascius bitcoins, which is why I am asking. Thanks!
8  Economy / Speculation / . on: December 21, 2013, 11:09:57 AM
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9  Bitcoin / Bitcoin Discussion / Re: GUIDE: Securely storing large amounts of bitcoin (brain wallet/paper wallet) on: December 06, 2013, 06:01:13 PM
The methodology below avoids having to download the whole blockchain to a dedicated offline computer (which is required with Armory).

That's wrong. The offline Armory does not use the blockchain or bitcoin-qt. Very low system requirements.

Your steps look good, but probably are too complicated for the majority of users. Also it forces you to reuse one address.

If you plan to do frequent transactions and have enough space for block chain and Armory database, you should check out Armory.

Oh I didnt realize. I'll update the main post. I mainly chose this method because it doesnt involve additional software or hardware, simply a USB with linux on it.

In regards to the number of addresses, you just generate as many as needed. I personally don't spend any of my cold storage coins very often, so generating 5-10 addresses lasts me quite a while. For those who are wondering why this matters: when spending from your savings, it is good practice to send any change/leftover amount you aren't spending to a fresh offline address (this gives increased security and privacy).

I think this is a useful post anyways. Smiley Thanks I'll save it. When it's optimised with feedback from the crowd I would like to 'copy' it and mention you a author of this article on my blog. Would you approve this? Thanks in advance, and again, nice useful post. Thanks!  Cool

Glad you found it useful! And sure go for it Smiley


@Samaney - I will answer your questions in full when I have a little more time. It is good you are taking the time to do your research!
10  Economy / Service Discussion / . on: November 24, 2013, 12:38:24 AM
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11  Bitcoin / Bitcoin Discussion / GUIDE: Securely storing large amounts of bitcoin (brain wallet/paper wallet) on: November 22, 2013, 02:24:22 AM
I wrote most of this guide a while back, and decided to finally finish it. The main goal here is to have a relatively simple way of creating a secure offline wallet entirely in your control. The methodology below avoids having to install additional software or download the whole blockchain to a dedicated offline computer (which is required with some offline storage methods). After practicing a few times, the steps below can be executed from scratch in 15-30 minutes.

Please let me know if you have feedback on how to make it better! Also, I highly recommend trying the whole process several times with small amounts until you are comfortable with it and understand all of the steps.

Creating a secure offline bitcoin wallet

  • Step 0:
    This is step is for brain wallets only.

    Spend some time thinking of a secure, memorable passphrase.
    The passphrase MUST BE something unique to you with at least 8 words. DO NOT USE something from a book, movie, poem, etc.
    Basically, if the passphrase can be found in (or easily generated from) any existing media, your funds will be at risk.

    An example of a decent passphrase formula:
    [your mother's birthday multiplied by your favorite number] +
    [every other word of some obscure phrase that holds special meaning to you] +
    [your home phone number when you were a kid] +
    [the first 5 words of your best freshman year english paper, ASSUMING IT ISN'T SEARCHABLE ONLINE]

    You should save clues to this passphrase that are only helpful to you in several safe places.
    Also practice regenerating the private key using the passphrase on a regular basis (every month or so), just to make sure the phrase stays fresh in your mind.

  • Step 1:
    Buy two USB sticks.

  • Step 2:
    Download ubuntu desktop ISO (12.04 is current Long-term supported version, at the time of this writing)
    http://www.ubuntu.com/download/desktop

  • Step 3:
    Download a USB linux installer.
    http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/

  • Step 4:
    Plug in brand new USB, and run the USB linux installer program (from step 3) to install a fresh copy of linux OS on the USB drive.
    Select the linux version matching the iso you downloaded, press create (see pendrivelinux.com instructions).

  • Step 5:
    Save the bitaddress.org webpage to the second USB (or to your desktop).

  • Step 6:
    THIS IS VERY IMPORTANT: Make sure networking/internet is completely off/disconnected.
    Turn off PC, and then re-boot from linux OS on your USB.
    To do this, I had to press the f2 during system load screen (specific key may differ by manufacturer).

  • Step 7:
    Locate your offline copy of bitaddress.org (from second USB or harddrive).

    If creating a brainwallet, then go to the brainwallet tab, and input your secure passphrase to generate your new private/public key.
    Quadruple check for typos and correctness. Record the public key(s) and save them in a few places.
    You can start by copying the new public addresses to a text file on your second USB.
    You do not need to keep the public keys private, unless you don't want people knowing what address has your coins.

    If creating a paper wallet, then navigate to the paper wallet tab. Print out as many paper wallets as you need.
    I recommend make a few copies of each and storing them safe places (locked, fireproof safe in your closet, parent's house, bank deposit box, etc).

    NOTE: you may wish to repeat this step several times, so that when accessing/redeeming a savings wallet only part of yovery,avings are at hand, and you do not have to repeat the offline wallet creation process.
    In a perfect world, you shouldn't re-use a long term savings address that has been spent from.

  • Step 8:
    Fully wipe the USB stick. This isn't 100% necessary, but if you are feeling extra paranoid, it won't hurt. The main drawback to doing this is that you then must re-install linux onto the USB (step 4).



Securely spending your offline funds

  • Step 1:
    See steps 1-4 above.

  • Step 2:
    In addition to bitaddress.org, save a local copy of brainwallet.org to your second USB or hard drive.

  • Step 3:
    Save to your extra USB (or hard drive) the receiving address that you wish to send your saved funds to.

  • Step 4:
    Retreive transaction history for your savings address by replacing [YOUR_ADDRESS] in the following URL with your actual public key:
    http://blockexplorer.com/q/mytransactions/[YOUR_ADDRESS]
    Copy the transaction history (text on the page from above URL) to a text file and save to your extra USB.

  • Step 5:
    THIS IS VERY IMPORTANT: Make sure networking/internet is completely off/disconnected.
    Turn off PC, and then re-boot from linux OS on your USB.
    To do this, I had to press the f2 during system load screen (specific key may differ by manufacturer).

  • Step 6:
    Open offline copy of bitaddress.org
    Type in your memorized passphrase on the brainwallet tab to retrieve your private key.
    Copy this and close the page.
    Paper wallets can skip this step, simply type in the private key from your paper wallet.

  • Step 7:
    Open offline copy of brainwallet.org, and navigate to transaction tab.
    Paste your private key into the correct field (labeled private key).
    Paste the receiving address (public key) you wish to send funds to into the destination address field.
    Open the text file containing the transaction history for your savings address that you are spending from.
    On the brainwallet.org page, click "edit input" and paste in the transaction history.
    Right above, it should say "Use history from" and give two options. Choose "Bitocin block explorer".
    The page should use the transaction history to figure out how much BTC you have available in your savings address.
    Double check this value. Then, input how much you want to send to the receiving address.
    Click the + button to add an additional receiving address.
    Take the left over coins (the "change"), subract a small fee and send that amount to a brand new savings address you have created.
    If you want, you can send the leftover amount back to the original address, but this is a tiny bit less secure (and reduces privacy).
    Input the small fee into the fee field. Triple check everything.
    If it looks good, click "re-sign" transaction and copy all the text in "raw transaction" field into a text file, and save this to your second USB.
    It is ok if someone sees this raw transaction data, they cannot steal your private key from it.

  • Step 8:
    Turn off computer, remove the USB that has linux on it. Reboot to your normal OS, and reconnect to the net.
    Open the website https://blockchain.info/pushtx.
    Copy the "raw transaction" data from previous step into the big text field, and hit "submit transaction".
    Your funds are now on their way! You can track them by exploring your address with blockchain.info search.


Notes

  • I very, very strongly recommend doing both processes listed above at least 2 or 3 times with SMALL amounts of bitcoin that you are comfortable losing. Do this until it all makes sense, and you understand what is going on.
    Then feel free to make you actual savings wallet! =)
12  Economy / Speculation / . on: November 09, 2013, 05:34:05 AM
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13  Economy / Speculation / . on: September 16, 2013, 06:06:43 PM
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14  Economy / Trading Discussion / Re: Discussion for MtGox trade data downloader on: August 16, 2013, 11:58:28 AM
Glad you've found it useful Smiley Yes, that's right. Here's an example of one script that's already been created - http://cahier2.ww7.be/bitcoinmirror/phantomcircuit/. This is a different format though, and doesn't store all the data (I did however port this to an export format). You'll need to determine which field in the API maps to which field in the BQ database, and fill in some that isn't included in the API (Bid_User_Rest_App__ for example).

There are some discrepancies with the API data - the missing fields, data being split into individual currencies, currencies occasionally being silently added, gaps in the API data, etc. Whilst this shouldn't be too much of a problem for your actual data processing, it could cause problems if you ever want to update from BQ again. I suggest that you instead insert the data from the API into a new table (say, dump_live). You can then create a view from a union between dump and dump_live, delete the obsolete index on dump, and index the view (Money_Trade__ ASC,[Primary] DESC,Currency__ ASC). This will allow you to still access all the data fairly fast, but without corrupting the BQ dump. If you don't mind an extra 200mb, you can leave the index on dump. My tool will recreate this index if it doesn't exist, so it might be easier and more efficient to just leave it.

I've actually given thought to putting this in the official tool, hence the insights I had above (I'm not sure when I'll have enough time to do that though, it would mean changing quite a lot of the tool), so if you want any help with your script let me know, especially as I've also written documentation on the MtGox API v2, so I can help you map the API data to the BQ schema and get around the data jumps Tongue

I ended up putting my trade analysis work on hold for a while, but I wanted to stop by and mention that I was able to get the remainder of the data using the API and add it to my db just fine. Thanks again for all your help.

I was curious about the gaps in the API data that you mentioned, what type of gaps exactly are you talking about? I did some extremely basic verification and recreated a few candles for a few random days, and I got the same result as bitcoincharts.com (after filtering to USD trades properly).

In case anyone is interested, here is the python code I used to query the remainder of the mtgox data. You have to do it in 1000 trade blocks, so it is essentially just a nice wrapper on a long series of API calls:
Code:
import urllib2
import json
import csv
import time
import datetime

API_FETCH_URL = 'https://data.mtgox.com/api/2/BTCUSD/money/trades/fetch?since='

# mtgox API varname: postgres DB varname (from BigQuery dump)
VAR_MAP = {
    'price_currency': 'currency__',
    'trade_type': 'type',
    'price_int': 'price',
    'item': 'item',
    'primary': 'single_market',
    'tid': 'money_trade__',
    'amount_int': 'amount',
    'date': 'date',
    'properties': 'properties'
}
VARS = [var for var in VAR_MAP.keys()]

def process_date(timestamp):
    return datetime.datetime.utcfromtimestamp(timestamp).isoformat(' ')

def fetch_trades(last_id= None, outfile= '', limit=False, noise=False):
    counter = 0

    with open(outfile, 'wb') as f:
        # create CSV writer object
        writer = csv.writer(f)

        # add header of varnames at top of file
        writer.writerow([VAR_MAP[var] for var in VARS])

        while True:
            # pause for 2 seconds between API calls to prevent getting banned by anti-DDOS
            time.sleep(2)

            # fetch trades after the most recent trade id, using mtgox API
            page_data = urllib2.urlopen(API_FETCH_URL + last_id)
            # read response from urlopen GET request
            json_response = page_data.read()
            # decode JSON data into python dictionary
            response = json.loads(json_response)

            if response['result'] == 'success' and len(response['data']) > 0:
                trades = response['data']

                if noise:
                    print 'Batch %04d -- ?since= %s, num trades: %d' % (counter + 1, last_id, len(trades))

                # write each trade as a separate line, using only trade values for the vars in the list VARS
                # for date, convert from timestamp into ISO str format (UTC) to match date column in postgres DB
                writer.writerows([[trade[var] if var != 'date' else process_date(trade[var]) for var in VARS]
                                  for trade in trades])

                # set last_id to the tid of the last trade, so we can fetch next batch of trades
                last_id = trades[-1]['tid']

                counter = counter + 1
                # if limit parameter is in use, then only do as many batches as specified
                if limit != False and counter >= limit:
                    break
            else:
                print '\n**********'
                if response['result'] == 'success':
                    print 'SCRIPT END -- last trade reached'
                else:
                    print 'SCRIPT END -- API call failed'
                print '**********'
                break

if __name__ == '__main__':
    username = 'name'
    fileame = 'mtgox_recent_trades.csv'
    # id of last trade from BigQuery dump
    last_dump_trade_id = '1369319572499520'
    outfile = 'c:\\users\\%s\documents\\data\\mtgox\\%s' % (username, filename)

    fetch_trades(last_id= last_dump_trade_id, outfile= outfile, noise= True)
15  Other / Archival / Re: delete on: August 03, 2013, 09:12:49 PM
As a rare visitor to the altcoin forum, I am mildly intrigued by the idea of this thread. I second EletricMucus' suggestion of starting with the least novel/lowest effort coins. Although I suppose that doesn't narrow it down that much  Wink

I also agree with those demanding less huff-puffing, more slaying
16  Economy / Trading Discussion / Re: Discussion for MtGox trade data downloader on: July 16, 2013, 11:08:38 PM
So I am teaching myself how to use Postgresql (among other things), and I thought "what better way could there be than finally getting around to messing with the mtgox historical trade data?" (I had been wanting to analyze this data for sometime). After searching around for a while, I came upon this thread.

Thank you so much for this awesome tool! You have saved me much time/effort Smiley It was very easy to start a dump, and the green bar is moving to the right currently so it looks like it is working! Just curious, the easiest way to fill in the missing data (as the Big Query db is not yet being updated regularly) would be to fetch trades with IDs after the ID of the last trade in the dump, yes? I was thinking writing a small python script using the API commands as specified in this post: https://bitcointalk.org/index.php?topic=178336.msg2067244#msg2067244
17  Bitcoin / Press / 2013-04-29 Forbes: Collected Quotations Of The Dread Pirate Roberts on: May 01, 2013, 04:17:51 AM
http://www.forbes.com/sites/andygreenberg/2013/04/29/collected-quotations-of-the-dread-pirate-roberts-founder-of-the-drug-site-silk-road-and-radical-libertarian/
18  Bitcoin / Bitcoin Discussion / Everything Is Rigged: The Biggest Price-Fixing Scandal Ever on: April 26, 2013, 02:00:55 AM
http://www.rollingstone.com/politics/news/everything-is-rigged-the-biggest-financial-scandal-yet-20130425
19  Economy / Speculation / . on: April 24, 2013, 05:50:16 AM
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20  Economy / Speculation / . on: April 23, 2013, 08:37:44 PM
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