Our (National Capital Cactus and Succulent Society) Annual Show has an entry category called "Collections" in which groups of related plants are entered. Since we have very few lithops growers in the society, I always try to enter a 'collection' of my lithops. Lithops are always popular with show visitors, many experiencing them for the first time. Young visitors are particularly excited by these 'stone-like' living things, while it sometimes takes a bit of convincing for older visitors to believe they really are plants.
Clockwise from upper left, Lithops dorotheae, Lithops karasmontana, Lithops lesliei var. hornii, Lithops bromfieldii var. insularis, Lithops bromfieldii, Lithops lesliei var. venteri.
Included as part of the entry was information describing lithops, their morphology, growth cycle, and native habitats. One of the great enjoyments of the annual show is discussing the wonderful world of succulent plants, including lithops, with the show visitors, many of whom have never seen these strange and unusual plants.