Claire is rather tall so I would estimate 1 yard of linen for the bodice and 4 skirt lengths for the skirt which makes about 7 yards of the silver linen (assuming 44″ width). Two yards of the cream silk for the sleeves and stomacher. I don’t know if the whole petticoat was cream silk – original ones generally were not – the fashion fabric was used where it could be seen and muslin or linen on the back. Assuming cream silk was used for the whole thing, about 5 yards of silk for the petticoat (assuming 44″ width). That’s about 12 yards of fabric. It doesn’t look to me like the pocket panniers Claire wears in the bedroom scene were the same underpinnings worn under the dress. It almost looks like a Civil War crinoline and a bum roll as the dress pouffed way out in the back which it would not have done had panniers been used. I also assume she wore an under-petticoat which would have been linen or cotton. My Civil War dresses probably weigh 3 or 4 pounds – silks less, wools a bit more.