68438 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":40.626605,"wof:name":"68438","counts:names_total":0,"wof:placetype":"postalcode","mz:is_current":1,"wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102083503,"localadmin_id":404519939,"locality_id":85973565,"postalcode_id":554774821,"region_id":85688563}],"mz:is_deprecated":0,"lbl:latitude":40.626605,"geom:area":2.7E-5,"geom:longitude":-96.744615,"wof:id":554774821,"counts:concordances_total":1,"geom:type":"Polygon","wof:lastmodified":1611185197,"wof:belongsto":[102191575,85633793,102083503,404519939,85973565,85688563],"wof:concordances":{"gp:id":"12787676"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"12589192","geom:area_square_m":251363.557142,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-96.748318,40.624375,-96.74046,40.628501","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-96.744615,"wof:geomhash":"52f078d70d1a4bd457b1268e0e89e504","wof:parent_id":85973565,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu","mz:postal_locality":"Sprague"}