Royal Worcester purchased the Royal China Works only a couple of years before this was made in 1900. The date letter J for 1900 is under the factory mark on the base.
I have called this a flask instead of a bottle, not sure why perhaps because it's not glass. It's decorated in the well-known blush ivory style with tiny enamelled "jewels" on the flowers. It doesn't have a stopper although I think it probably did have one and there is a cork in the neck now.