Singer seal dating
The gold leaf on the machine varies slightly in pattern over the years as well.
The early tension adjustment and throat plate are un-numbered, while the later tension adjustment is numbered and black rather than chrome.
The later throat plate has seam allowance markings.
Dating of the model 221 is quite easy using the serial number stamped on the underside of the machine.
The most- interesting designs were seals from machines marketed during various expositions.The 221K was black or a shiny white and has a shorter bed.A smaller number of machines in other colors exist, including a light tan color produced in Great Britain and a matte black produced in the United States.Machines in good condition can still be found at bargain prices in garage sales and auction houses.Advertisements in quilters' magazines bring higher prices.