A primary characteristic of 19F-MRI of pulmonary ventilation is the short in vivo T2* of the inhaled imaging agent caused by the inhomogeneous magnetic environment proximal to the alveolar walls. This study describes two novel methods for fabrication of phantoms that mimic the physical and magnetic properties of alveolar tissue. In both cases the perfluorinated gas phase imaging agent is suspended in a stable microporous foam medium. The fabrication techniques permitted precise control of either bubble size or gas/liquid ratio. Highly monodisperse stable foams were formed with a perfluoropropane T2* of 2ms, comparable to that measured in the human lung.