plack / plaque [plæk]
plack – n. – 1. a small coin from the 15th and 16th century; 2. a negligible amount money; 3. a large pile of hay ready for storage
plaque – n. – 1. something that is flat or in the form of a tablet i.e. decorative badges, plates etc.; 2. a counter used in gambling; 3. a well-demarcated area of abnormal tissue; soft; 4. soft deposits on teeth