Lost object horary is a big challenge for me but for reference I used this web page.
http://www.skyscript.co.uk/wit.html
I’m keeping it simple and using 2H for your possessions, because this gold chain is
yours, via inheritance or otherwise.
The quote from the webpage that stuck out was “look for themes or indications which are highlighted through repetition.”
Your 2H ruler is in a mutable sign within 30 degrees of the ascendant ruler, which indicates that the chain is inside your home.
I’m also seeing that it is in a fire sign, specifically Sagittarius, and this indicates that it’s likely near a heat source. Sagittarius and Fire signs in general indicate an eastward direction. The sun is in a 5° conjunction and represents reception rooms, halls, cloisters, or near mens’ things. Sagittarius indicates high rooms or grounds. Mutable signs represent closets, covered spaces, or rooms within rooms.
I’m wondering if you don’t have an upstairs closet or storage cubby where objects go to rest when they aren’t being used. Maybe the closet is unusually warm because it’s right next to a heating unit. I get the sense it would be in a part of your home that doesn’t get a lot of foot traffic. It could be in the East corner of your house, or the east side of the room itself.
That’s my take, I do hope you find it. Please keep us updated