This class comprises physical material in a relative stability of form (substance) within a specific spacetime volume (unity, extend). The spatial extend of a S22 Segment of Matter is defined by humans usually because the constellation is subject to a specific interest for and investigations of the geometric arrangement of physical features or parts of them on or within the specified S22 Segment of Matter. It comes into existence as being an object of discourse through S4 Observation or declaration and is restricted to the time span starting after the last change through an S18 Alteration before the S4 Observation or declaration and ending with the next S18 Alteration Event (identity). A S22 Segment of Matter exists as long as there is no modification of the geometric arrangement of its particles. Therefore the temporal boundaries of the defining Spacetime Volume are given by two S18 Alteration events. The history of a S22 Segment of Matter started with the first S17 Physical Genesis event that deposited still existing matter within the defined spatial extend. The collection of all S18 Alteration events represent its history. Some of the events will not leave any physical material within the S22 Segment of Matter. (to be elaborated further)