Fish Soup with Oysters and Artichokes

For the fish stock: Rinse and chop the fish bones. Rinse and coarsely chop greens. Melt butter in a saucepan. Add the fish bones, vegetables, thyme and white peppercorns, and season with salt to taste. Allow to cook until the vegetables brown slightly. Stir in the wine and add enough water to cover everything. Simmer for 20 minutes. Line a fine sieve with cheesecloth and pour the stock through. Do not press the solids or else the stock may become cloudy. Pour the stock in a pot and reduce to 1 liter (approximately 4 cups) of stock. 

For the soup ingredients: Quarter the artichoke hearts. Rinse the oysters and open. To open the oysters, place each one on a clean towel with the arched side facing down. Pierce the hinge with an oyster knife and twist to open. Remove the top shell. Use a knife to loosen the oysters from the shells. Strain the oyster water through a fine sieve into the fish stock. Add the artichokes and oyster meat to the stock and simmer for 4 minutes.