Update 6/12/11
After much searching, I have finally found the earrings that Kate was wearing.
They are Kiki McDonough from her 'Grace Collection.' The earrings are set in white gold with a white topaz center stone surrounded by diamonds.
Update 3/11/2013
Kate's gloves have been ID'ed (thanks to 'Tatiana's Delights' on FB). They are by Fownes and are no longer available.
The gloves are soft Nappa leather with a red cuff trim. The lining is a lambswool & angora blend knit.