91355 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":34.424653,"wof:name":"91355","counts:names_total":0,"wof:placetype":"postalcode","mz:is_current":1,"wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102086957,"postalcode_id":554751969,"region_id":85688637}],"mz:is_deprecated":0,"lbl:latitude":34.440248,"mz:postal_locality_alt":["Santa Clarita","Newhall"],"geom:area":0.003973,"geom:longitude":-118.589246,"wof:id":554751969,"counts:concordances_total":1,"geom:type":"Polygon","wof:lastmodified":1611184346,"wof:belongsto":[102191575,85633793,102086957,85688637],"wof:concordances":{"gp:id":"12796000"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"2510684","geom:area_square_m":4.0518825792412E7,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-118.659626,34.378685,-118.537841,34.461148","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-118.643992,"wof:geomhash":"f6cbf761a055d90eb550837caf254727","wof:parent_id":102086957,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu","mz:postal_locality":"Valencia"}