Re:请教两个问题
Dear Kaythomas
Sure, it can be singular or plural. When it is singular, it refers to a colletction of valuable things such as gold, silver and jewllery: e.g. buried treasure.
When it is countable and thus can be in plural form, it denotes a highly valued object. e.g. some priceless art treasures.
I am sorry, I don't what you mean exactly regarding the 'It is said......' structure. Could you please let us have a look at your original text?
regards