Using a deep saucepan, fry salt pork or bacon slowly. Remove and add diced onion. Cook on low heat until onion is soft. Add clam juice, diced raw potato and enough black pepper to satisfy your taste. Cover pan, bring to steaming point,lower heat and cook at least 15 minutes.
Remove cover, add minced clams, stir to mix. Cook about 10 minutes with cover off, allowing clams to simmer along in cooked potato mixture.
Add milk and butter and heat to serving point. Do not boil. Taste for seasoning and add salt and more pepper as needed.