What is the name for butter and chocolate that used for exhibition?

What is the name for butter and chocolate that used for exhibition? The one that won’t melt for a long time at the room temperature. I’m just curious to know the name for each.
no, it’s not concoct chocolate. I remember its “xxx” chocolate and “xxx” butter”. I need name for the butter and for the chocolate. I forgot the name but i know each has a specific name.