Spend Key - General Info
One of the two pairs of private and public cryptographic keys that each account has, with the private spend key used to spend any funds in the account.
The private spend key is a 256-bit integer that is used to sign ULTRAPOINT transactions. With the current deterministic key derivation method of the official wallet, the private spend key is also an alternate representation of the mnemonic seed. It can be used to derive all other account keys.
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