I have seen a couple opinions out there...
1. Anything over 20 years old (currently this would mean anything before 1991)
2. Clothing and accessories from the 1920s to 1980s; anything before 1920 is considered antique
How can you tell is something is vintage?
The easiest answer to this question is look at the quality. Many vintage items were hand-made rather than the mass-produced clothing we see today.
Take a look at the tag and look for:
- Union labels
- Lot or Style number
- Made in the USA
- Unique and decorative labels
Also pay attention to sizing. Vintage sizing is typically a size or 2 smaller than what it is today (ie a vintage size 6 will fit like a modern-day size 2). This phenomenon is called "vanity sizing" but that's a topic for another post...
Take a look at your jewelry carefully. Quality, again, is another major factor. You might see some wear or discoloration also in the strings or clasp. Signed pieces are usually a tip-off since jewelry was far-less mass-produced than it is these days. Trends are another thing to take note of: brooches, for instance, are less popular (though coming back) than they were (think: cameos).
Vintage and "retro" fashions are seeing a major comeback. If you are unsure if an item you have is truly "vintage" feel free to email me with some info and pictures and I'll be happy to help!
The Vintage Fashion Guild is a fabulous resource, check it out!