All our rocks are carefully selected for educational study. They come in labelled trays. The trays are normally 3″ x 2″ size depending on the rarity of the specimen. Average specimen size is shown below. These are ideal for classroom teaching and are a size that can be easily passed round the classroom for students to get a feel for each type.
Scoria is a highly vesicular, dark-colored volcanic rock that may or may not contain crystals. It is typically dark in color, and basaltic or andesitic in composition.