private static String invalidTypeErrorMessage(final String invalidEcCurve) {
    return invalidEcCurve
        + " is not in the list of valid elliptic curves "
        + getEcCurvesListAsString();
  }
Is default signature algorithm.

@param signatureAlgorithm the signature algorithm
@return the boolean
crypto/algorithms/src/main/java/org/hyperledger/besu/crypto/SignatureAlgorithmType.java