The focus of this introductory assignment was to parametrically develop a form inspired by an object in nature that describes both structure and surface. A leaf was chosen whose ribbed veins and vaulting surface membrane form an integrated structural and surface system. Parameters of size, spacing, and amplitude of vaulted surface/ribbing were identified, and then developed through successive parametric iterations, evolving towards ever greater complexity and variability of form. Models were 3d printed in plaster to provide a physical atifect for examination and feedback to influence further developments of the parametric model. Finally, two successive iterations of cementitious casts were executed based off of our formal and structural investigations. The two-part molds were CNC milled from high density sign foam, following tool paths generated by a Rhino model in MasterCAM. The final Rockite cast reached the limits of the structual capacity of the material, resulting in a fragmented castGroup Project with one partner.