Laravel 5 UnexpectedValueException em resposta à consulta devido ao uso de dados POINT

public function rentals($id)
{
    // Retrieve all rentals within a region and the locations spatial data
    $rentals = DB::table('rentals')
                 ->join('regions', 'rentals.region_id', '=', 'regions.id')
                 ->join('rental_locations', 'rentals.rental_location_id', '=', 'rental_locations.id')
                 ->select('*')
                 ->where('rentals.region_id', '=', $id)
                 ->groupBy('rental_location_id')
                 ->get();


    return collect($rentals); // or return $rentals
/* Not necessary
    // Create a collection from the array of query results
    $rentals = collect($rentals);


    // Laravel is set up to return collections as json when directly returned
    return $rentals;
*/
}