Here is what my researched produced -
Your tray dates ca 1920s. It could be Iranian but is definitely Persian. It appears to be tarnished copper - see green discoloring in the engraving. This green/aqua color is typical of old copper.
See the following photo. It is smaller than yours but is scalloped and more highly engraved than yours.
The asking price for the example is $465.
We can take this as a low end of comparables. I found others that were priced higher...
My best estimated retail value range would be $465-750 assuming good condition and depending on geographic location.
Online auctions like eBay generally bring wholesale selling prices.
If you would like to sell close to estimated retail, some ideas are:
The internet has your largest audience of buyers. Place small ads on these sites or set up your own small store on these sites.
These sites carry antique as well as vintage items.
Accept PayPal only.
Etsy.com - small fees - 20 cents to list plus 3.5% final price.
Or your nearest CraigsList.com where you can list items for free. Accept cash only.
These sites are excellent and more upscale but fees are higher. I only recommend them if you have several items to sell.
Trays can be tricky to ship. Usually a wood crate needs to be built. UPS has done this for me in the past. Be sure to charge enough for shipping. You probably should take the tray to the UPS store (or your chosen shipper) to get estimates to various locations where you are advertising.
In general, a private seller to a dealer, via consignment or at auction can expect 30-50% of estimated retail value.
Insurance replacement values are usually about 10% more than retail values.
I hope I have helped you.
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