Our Lady of the Rosary with SS. Catherine of Siena and Dominic
Church of St. Peter Martyr, Murano, Italy
From the gestures of Mary and the child it is clear that originally they were handing rosaries to the two saints, but as in so many other sculptures like this the rosaries have been lost.
A very similar sculpture in Venice's Gesuati church also pictures St. Catherine with a crown of thorns.
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More of St. Dominic
More of St. Catherine of Siena
More of Our Lady of the Rosary
Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.