The period of time specified could be quite quick, nevertheless, for example 10 minutes (as is the situation with JM Bullion). Dealers do this to try to secure on their own from quickly switching prices. Physical treasured metals like gold certainly are a hedge to the standard banking system. https://goldandsilverbulliondalla71468.jts-blog.com/33240298/5-easy-facts-about-gold-silver-bullion-coins-dallas-described