Viewing is not allowed. However, you can request for a redemption and choose to either self-collect or have it delivered (shipping insurance and premium manufacturing fees are applicable).
Related articles:
Where are my bullion physically stored?
What is the fee for storage per year?
Are my bullion holdings fully insured?http://help.stackermarket.com/en/articles/5355742-are-my-bullion-holdings-fully-insured
Is there proof my bullion is physically held in a vault?