My name is ***** ***** I would be happy to help with your curio shelving. Thanks for the helpful photo, I can see exactly what you have.
This particular form of furniture with tiers of graduated shelves is known as a "whatnot" or a "whatnot stand" after the term the Victorians used for small decorative items that this useful and ornamental shelving provided the perfect display for.
The lathe turned spindle supports and decorative finials, and the fretwork backboards with openwork rococo scrolling date yours to the last decade or so of the 1800s.
Looking at comparables in the recent auction sales records, this example, similar to yours, sold for $200 which is probably about representative.
I would give yours an auction value in the range of $180 - $270.
It therefore has a full retail value (if you saw it for sale in an antique store, for instance) of $500. This is also the replacement value for insurance purposes.
I do hope this helps!
Please let me know if you like me to explain or expand on any of the above, I would be glad to.