What is the best word to describe an "object of importance" without inquiring about its past? (i.e. not memento)

talisman - anything whose presence exercises a remarkable or powerful influence on human feelings or actions.

The more "literal, core" sense is a stone, ring, or other object, engraved with figures or characters supposed to possess occult powers and worn as an amulet or charm, but it's often used more loosely as per the above definition (see these example written instances of "treasured talisman").

Treasure may be your best bet. I can't come up with a synonym for gift that conveys the nuance you've described. You may need to add a modifier to articulate the aspect of the gift that makes it worthy of worship, for example "an incomparable treasure." My advice, however, is to keep it simple.