rocaille | Description, History, & Facts | Britannica.com
https://www.britannica.com/art/rocaille
Rocaille, in Western architecture and decorative arts, 18th-century ornamentation featuring elaborately stylized shell-like, rocklike, and scroll motifs. Rocaille is one of the more prominent aspects of the Rococo style of architecture and decoration that developed in France during the reign of King Louis XV (1715–74).
Rocaille - Wikipedia
https://en.wikipedia.org/wiki/Rocaille
Rocaille was a French style of exuberant decoration, with an abundance of curves, ... which spread to Italy, Bavaria and Austria by the mid-18th century. ... in the complex frames made for mirrors and paintings, which sculpted in plaster and .... in 1748 turned French architecture in the direction of the more symmetrical and ...

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Note added at 32 mins (2018-11-05 16:57:11 GMT)
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From the V & A

Style Guide: Rococo
The Music Room from Norfolk House, St James's Square, London; Matthew Brettingham (architect), Giovanni Battista Borra (designer), Jean Antoine Cuenot (carver), James Lovell (chimneypiece, possibly, carver); 1748-1756. Museum no. W.70:1-1938. © Victoria & Albert Museum, London
The Music Room from Norfolk House, St James's Square, London; Matthew Brettingham (architect), Giovanni Battista Borra (designer), Jean Antoine Cuenot (carver), James Lovell (chimneypiece, possibly, carver); 1748-1756. Museum no. W.70:1-1938. © Victoria & Albert Museum, London

The Rococo style was used primarily in furniture, silver and ceramics, rather than architecture. It takes its name from the French rocaille (pronounced 'rock-eye'), which means the rock or broken shell motifs that often formed part of the designs. Rococo was fashionable from about 1730 to 1770.