/// <summary>Implicitly create a new coin</summary>
        private Coin CreateCoin(string sym)
        {
            var coin = new Coin(sym, Exchange);

            if (!m_coin_data.Contains(coin.Meta))
            {
                m_coin_data.Add(coin.Meta);
            }

            CoinData.NotifyBalanceChanged(coin);
            return(coin);
        }