Layer
narrower: Layer type
definition: A material entity which 1) is spatially continuous, 2) is composed of material of comparable thickness, composition, and physical properties, and 3) is physically distinct from adjacent portions of environmental material. (TIB, The Environment Ontology)
broader: Sample part
broader: Sample shape
type: Concept

Layer type
type: Concept
broader: Layer

Sample part
type: Concept
narrower: Layer

Sample shape
type: Concept
narrower: Layer