This is one of many portraits of Queen Elizabeth wearing a dress with numerous small slashes in the bodice. She holds a pomander by a cord.
There are a number of portraits of her wearing slashed dresses like this — see the Luminarium at: http://www.luminarium.org/renlit/elizface2.htm. This one was selected at random from them that is in a private collection. There are a number of similar images. She wears an escoffion and a reticulated veil while her dress is liberally slashed. This is a good example of using slashing as an ornament in dress. In many cases, the underlying cloth is white, but it is black in this example. The sewn borders of the slashes clearly show.