Good morning, Gena,

Thank you for contacting Mearto with your appraisal inquiry.
This could be Murano but there were other glassworks in Venice so it may be safer to say this is Venetian rather than Murano. This is a lovely sconce; the different colors are somewhat unusual and I think make it more appealing. Sconces were typically sold in pairs, so it is a bit of a shame that you just have the one.
Here are a few recent auction sales of comparable sconces that I have used in researching the value of yours, and so you have an idea of the current market for these. I have put the price realized in parenthesis before the link because that information isn't given unless you have an Invaluable account, though you can see the estimates in the link and it may be useful to you to see what sconces have been estimated at as well as the price they sold for:
($150) https://www.invaluable.com/auction-lot/pair-venetian-glass-mirror-wall-sconces-41a420fb1c
($562) https://www.invaluable.com/auction-lot/a-group-of-four-worked-and-etched-venetian-glass-1664d00a70
($340) https://www.invaluable.com/auction-lot/a-pair-of-three-light-murano-glass-sconces-muran-43f42eabb3

Based on the photographs and information provided, and subject to examination, you have a
Venetian Multicolored glass and etched mirrored two-light wall sconce
Probably late 19th Century
30 inches tall, 18 inches wide
PROVENANCE: acquired through an estate
CONDITION: wear appears commensurate with age and use; client purports one candle arm has a loss
$150-200 (represents a fair market value for auction purposes; retail or asking price may vary).

Please let us know if you have additional items to appraise, and thank you for using Mearto.