If you allow another person to borrow your property and it is damaged or stolen while in their possession it is likely that the property will be covered by your insurance, but you should verify with your specific insurance carrier first. If it is not covered, then the property may be covered by the other person's insurance. Many insurance policies will cover someone else's property if it is damaged or stolen from the borrower's home.
Each insurance policy will have its own restrictions and coverage rules. You should always ask questions and make sure you understand the insurance coverage before you buy.
Renters insurance is a great way to protect your personal property from damage or theft. Many types of renters insurance will cover items that are located at a place other than your dwelling but will only cover your property up to a certain amount. The amount that is covered is based on the amount of coverage you agreed upon when you purchased the policy, minus the deductible.