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Bitcoin Gold is a distributed digital currency. It is a hard fork of Bitcoin, the open source cryptocurrency. The stated purpose of the hard fork is to restore the mining functionality with common Graphics Processing Units (GPU), in place of mining with specialized ASIC (customized chipsets), used to mine Bitcoin.

Bitcoin Gold
Ticker symbolBTG
Initial release0.15.0.1 / 12 November 2017 (12 months ago) (2017-11-12)
Latest release0.15.0.2 / 6 January 2018 (10 months ago) (2018-01-06)
Development statusActive
Forked fromBitcoin
Written inC++, Qt
Operating systemWindows, OS X, Linux
Developer(s)Bitcoin Gold Organization
Source modelOpen source
LicenseMIT License
Ledger start3 January 2009 (9 years ago) (2009-01-03)
Timestamping schemeProof-of-work
Hash functionEquihash
Block reward12.5 BTG (approximately to mid 2020), halved approximately every four years
Block time10 minutes
Block explorerBitcoinGold Explorer BTG EXPLORER
Supply limit21,000,000 BTG

ASIC resistant GPU powered mining provides a solution, as this kind of hardware is ubiquitous, and anyone can start mining with a standard, off-the-shelf laptop computer.

Bitcoin Gold was hit by double-spending attack on May 18, 2018.[1]


The forkEdit

The hard fork occurred on October 24, 2017, at block height 491407. The Bitcoin Gold team used ‘post-mine’ - a mining of 100,000 coins after the fork had already occurred. The team did this via a rapid mining of approximately 8,000 blocks at 12.5 BTG per block. The bulk of premined coins have been placed into an ‘endowment’, and according to the developers will be used to grow and maintain the BTG ecosystem. However, of the 100K coins, some five percent were set aside as a bonus for the team, or about 833 coins for each of the six members.

Differences from BitcoinEdit

Bitcoin Gold uses the memory hard equihash as its proof-of-work algorithm instead of SHA-256.[2] Otherwise, the project follows the guidelines of the Bitcoin core project.

May 2018 attackEdit

In 2018, Bitcoin Gold (and two other cryptocurrencies) were hit a by a successful 51% hashing attack by an unknown actor.[3] The attackers successfully committed a double spend attack on Bitcoin Gold, a cryptocurrency forked from Bitcoin in 2017. Approximately $18.6 million USD worth of Bitcoin Gold was transferred to a cryptocurrency exchange (typically as part of a pair transaction in exchange of a fiat currency or another cryptocurrency) and then reverted in the public ledger maintained by consensus of Proof-of-Work by exercising a >51% mine power.[3][4][5][6]


  1. ^ "According to a post on the Bitcoin Gold forums, the attacks have started taking place since last Friday, May 18.",
  2. ^ Aaron van Wirdum (Oct 11, 2017). "Bitcoin Gold Is About to Trial an ASIC-Resistant Bitcoin Fork". BitcoinMagazine.
  3. ^ a b "Bitcoin Gold Hit by Double Spend Attack, Exchanges Lose Millions". CCN. 2018-05-23. Retrieved 2018-05-24.
  4. ^ "Bitcoin Gold loses millions as it is hit by a double spend attack". Fast Company. 2018-05-24. Retrieved 2018-05-27.
  5. ^ Osborne, Charlie. "Bitcoin Gold suffers double spend attacks, $17.5 million lost | ZDNet". ZDNet. Retrieved 2018-05-27.
  6. ^ "Bitcoin Gold Responds to Recent Double Spend Attack". CCN. 2018-05-25. Retrieved 2018-05-27.