In order for me to properly assess what you have I will need to see images and clear, in-focus close-ups of the mark.
Please send the photos at your convenience. There is not an extra charge to provide more pictures here.
You can try emailing your images to *****@******.*** and write “For Nora/Antiques” in the subject line of the email.
Photos sent by email do not arrive to me directly nor instantly, they get forwarded to me by admin.
I received the image, thank you. Your antique circa 1900 bent slag and decorative metal cased shade lamp by Royal Art Co with original base would sell for $900 - $1200 at auction on today's market.
Here is a link for you of a similar comparable to yours that sold for $1100:
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