(grob-property-description 'thick number? "thickness, in stafflinethickness.")
(grob-property-description 'thick-thickness number? "thickness, measured in stafflinethickness.")
(grob-property-description 'thickness number? "thickness, measured in stafflinethickness.")
(grob-property-description 'thick number? "thickness, in stafflinethickness.")
(grob-property-description 'thick-thickness number? "thickness, measured in stafflinethickness.")
(grob-property-description 'thickness number? "thickness, measured in stafflinethickness.")