Historical clue formulations

• Mexican silver city — 2017-08-24
• Mexican tourist city known for its silver — 2016-12-07
• Mexican silver center — 2010-11-25
• Mexican silverworks city — 2005-06-05
• Mexican silver mining center — 2004-06-16
• Mexican silverwork center — 1999-11-08
• Mexican silverwork center — 1998-11-28
• Tourist mecca near Mexico City — 1997-09-30