This remarkable, small vinaigrette or rectangular form is from China (or possibly of Chinese workmanship from Southeast Asia). It is covered on all sides (including the base) with the finest silver filigree. It is heavy for its size, on account of its double walls and the compartment hidden in the interior in which was stored absorbent material soaked in a fragrant oil such as clove or lavender oil.
The compartment inside is covered with a small hinged lid that is also composed of silver filigree.
The vinaigrette has a hinged lid. It also has an eyelet on one side which would have allowed it to be worn suspended on a chain as a pendant - eighteenth century European ladies would have worn the item and when their carriage drove over an exposed drain they could have reached for their vinaigrette to help them recover from the smell.
Most probably the vinaigrette was entirely gilded (gold-plated) but now only the interior retains the original gilding, which remains bright and vibrant.
Another Chinese export silver example (but with solid chased sides rather than with filigree) is illustrated in The Oriental Gallery (1994, no. 82).
This vinaigrette is in excellent condition. It is a fine and rare example.
References: The Oriental Art Gallery, 'Oriental Jewellery and Works of Art', 1994.