I have bitcoins stored on paper wallets that I created a few years ago and wanted to sell the associated bitcoin gold which ended up being more complicated than anticipated, so I wanted to detail my journey in case it helps others who may want to do the same.
Private keys are precious
If you have had a bitcoin paper wallet for any length of time then the paper wallet contains keys that hold bitcoin, bitcoin cash, and bitcoin gold (amongst other forks and snapshots). Redeeming and separating these coins presents a challenge: The private key is the same for each of them, so any software you expose the private key to could steal all of them.
Move the most valuable and most trusted coin first
It’s kind of like peeling an onion. First you expose your private key to move the bitcoins, then bitcoin cash, then bitcoin gold. I used this order because each step poses more risks of losing your coins, and so moving the coins by order of value minimizes the odds that coins will be stolen or lost.
First of all, I moved my bitcoins to a new wallet by sweeping them using the iOS app Bread Wallet’s import feature. This removed the bitcoins from the paper wallet. You can use any reliable bitcoin wallet to do this that has a sweep/import feature. Once I confirmed the bitcoins had been moved, I focused on bitcoin cash. Unfortunately, Bread does not support bitcoin cash, so I used the iOS Bitcoin.com wallet to import the bitcoin cash from the paper wallet just like I had done with Bread and btc.
Finally I had isolated the paper wallet to only bitcoin gold
While there was nothing else of value in the paper wallet besides bitcoin gold, I wanted to do the best I could to not compromise the keys in case a new fork retroactively gave the keys value, and also I wanted to do my best to make sure I did not lose my bitcoin gold since it did have some monetary value (~$300USD per coin at the time of writing). Lastly, I wanted to make sure that I did not permanently compromise my computer or phone in the process and perhaps lose other cryptocurrency due to that in the future.
Then it got more complicated than I had expected
After looking at Bitpie reviews and seeing that a user said it stole their money on the only English review in the iOS App Store, I decided I could not trust it. At the time of writing, that is the only iOS wallet available that bitcoingold.org lists as compatible.
Bitcoin gold core wallet currently does not support Mac and they list no supported Mac wallets at all.
Attempt 1: VMWare Fusion running Linux to install the bitcoin gold core wallet
I first went down the path of setting up a VMWare Fusion Ubuntu virtual machine and then attempting to install bitcoin gold core, but I discovered this approach would take a lot of time and more hard drive space than I was happy with. The blockchain torrent is over 100GB, so I gave up on that approach.
Attempt 2: Android Emulator on Mac
I chose NOX as an Android emulator, and downloaded Coinomi APK from their website. After installing NOX and then installing the Coinomi apk, I was running Coinomi on my mac in NOX and was able to setup a bitcoin gold wallet for the first time.
Once configured I used the “Sweep Wallet” option to move the bitcoin gold off the paper wallet and into the Coinomi wallet. Unfortunately the camera emulation in NOX did not work on my mac and so I had to manually type in the paper wallet private key. Regardless, it worked, and I was almost immediately able to send my bitcoin gold from Coinomi to my Bittrex account where I could then sell it for something else.