After a big purchase or gift of jewelry be sure you contact your insurance agent. Most homeowners policies limit coverage for personal valuables. So what this means for you is that the coverage in your homeowners policy could fall far short of replacement value if your 3 caret diamond or Rolex is lost or stolen.
Know that all policies are not created equal. So some homeowner insurance covers your possessions up to 50% of your total coverage limit, but others it may be significantly less or have a limit on your jewelry. In fact, most policies place limits on specific kinds of items -- promising to pay a maximum of, say, $1,500 to $2,500 for all of your jewelry in the event of damage or theft. O
Other categories that usually have reimbursement limits include silver flatware, firearms, coins, stamps and furs. (Read the "contents and additional coverage" section of your policy for the details.) Accidental loss is generally not covered. So if you lose your engagement ring, you're out of luck.
It is a good idea to raise your coverage limit and ensure that you're protected in case of loss as well as theft. Be sure to contact your insurance agent and ask either to add a rider to your policy or to "schedule" the item. (You may need a written appraisal, although a detailed receipt may suffice.) Once you set a value and schedule the item, you're covered for the full amount if it is lost, stolen or destroyed.
Source: http://www.kiplinger.com/article/insurance/T028-C000-S002-will-my-homeowner-s-policy-cover-my-jewelry.html#BY8ZeDR2H0Iz2bgw.99