1811 Half-Mourning Dress, French. Black dress, high white neck ruffle, black hat with white trim and white shoes. Jane Austen and her family would have worn this type of outfit when mourning a relative or friend. However, as black dresses, black tunics, and black lace shawls were popular throughout the Regency years, it is often hard to decide what was definitely made for mourning and what was simply fashionable wear. Fashion Plate via Journal des Dames et des Modes, or Costume Parisien.

In November, 1810, Princess Amelia, youngest daughter of George III, died. At the end of 1810 full mourning of complete black would have been worn but by the beginning of 1811, half mourning would still have been to respect the loss of a royal family member. Half-mourning allowed touches of silver, grey, mauve and white to be added to a mostly black outfit and would be worn after the period of full mourning was ended, times depending on the relationship to the deceased person. Garments and accessories could either be trimmed with black, jet jewelry worn, black ribbons added, or a layer of black net or gauze added to a dress or hat. 

Definition Half or Slight Mourning: Allowed touches of grey and white to be added to full, or deep, mourning ensembles. Some lustre, or shine, was allowed in fabrics and accessories. After a time, mauve or deep purple could also be worn. https://books2read.com/SuziLoveFashion1810-1814