Here are just a few quick easy-to-remember tips. These facts don't necessarily place a garment in a year, but they will help narrow it down.

SEW AND SEW

• The first practical sewing machine was invented in 1845. Not in general use immediately. If it has machine sewing, it’s post 1845.
  
  
• Machine chain stitch came first, followed by lockstitch. Lockstitch seams are rarely found prior to 1870.
  
  
• Hand-sewn construction (rather than hand finishing) and machine-sewn construction coexisted for years - until the 1880s, if not later.
  
  
• The zigzag machine was patented in 1873 and many were in use on a commercial basis by the 1890's.  1947 was the first year for use on a domestic basis for home sewing.
  
  
• The serger has been in use since the 1920’s for seam finishing. This is the overlock or serger thread finish we still use today on cut fabric edegs inside the garment.
  
  
• Hanging loops at the neck of jackets, blouses and so on, are usually of European manufacture.
  
  
• Hemming tapes generally denote North American manufacture. German manufacturers never used them.
  
  
• Circle stitching inside the cups of a bra is a good indicator that it’s from the 1950’s.

• The NRA (National Recovery Act) Blue Eagle label was used in the USA only from 1933-35. This label (noting compliance with the Manufacturing Codes) was used inside garments and dates them specifically to those years. The NRA was declared unconstitutional in 1935.
  
  
• The US National Labor Relations Act was passed in 1935. So these labels will be seen after that date.
  
  
• The ILGWU (International Ladies' Garment Workers' Union) was formed in 1900. It joined the CIO (Congress of Industrial Organizations) briefly in 1937. Rejoined the AFL (American Federation of Labor) in 1940. AFL-CIO merged in 1955. In 1995 ILGWU reformed as UNITE. Union labels will reflect these name and date changes.
  
  
• Look for labels in the side seams and even the hems of older garments.
  
  
• Country of origin labels came about in the USA following the McKinley Act, 1891.
  
  
• Garment Care labels began in 1971 in the USA. The current labels were introduced in 1983.
  
  
• International care symbols were developed 1971.
  
  
• The USA Textile Products Identifications Act, 1960 mandated the use of fabric content labels.
  
  
• The Fur Products labeling act of 1952 required an accurate description of fur. i.e. "Hudson Seal" became sheared muskrat.
  
  
• A small 'e' on the label of a pair of Levis denims means they were manufactured after 1971 and if a capital 'E' they are pre-71.

Here are just a few quick easy-to-remember tips. These facts don't necessarily place a garment in a year, but they will help narrow it down.

Watch pockets can be found on the waistline or waistband of dresses 1840’s-1880’s and elsewhere on the dress bodice from the 1880’s.

Cartridge pleating of the skirt at its waist is seen 1840’s-1860’s, fading out by the 1870’s.

Tiny piped armhole seams date a garment to the 1870’s or before and is rare after that.

Armholes were cut high and fitted in the 1970’s, and also 1950’s.

Three-quarter and seven-eighth sleeves were popular late 1930s, 1940s, and 1950s.

Diamond gussets in the armhole indicate 1950’s.

In 1942, men’s double-breasted suits in the USA lost their vests and became 2-piece due to the war effort.

• 18th century silk brocade with white grounds usually denotes English manufacture whereas silk brocade with yellow grounds usually means it's French.
  
  
• Rayon (known as artificial silk) was a French process developed during the 19th century. AKA Viscose (English process). The name Rayon was coined in 1924 and was used extensively for lingerie and light summer dresses until the 1950s when nylon became popular.
  
• Orlon®, trademarked by DuPont stared development  as Fiber A in 1941, but production did  not strat until 1950 in South Carolina. Boom years of production
• were the mid 1950s and 1960s.
  
• Dacron®, trademarked by DuPont and denotes numerous types of polyester yarn. Used in manufacture from 1953.
  
• Nylon was the first true synthetic developed by DuPont in the 1938, available to the American public in May 1940, used in stockings. Not used in clothing until well after WWII.
  
• Qiana®, a filament nylon used for woven and knitted fabrics was registered by DuPont in the 1970's.
  
• Spandex - first commercial use in 1959, seen in lingerie in the early 60's, but not in clothing much until the 80's. (Registered to DuPont as Lycra®)