That deep dent in the bottom
Why Do Wine Bottles Have a Punt?
That dent in the bottom of a wine bottle seems mysterious today. It began as a practical glassmaking feature that helped bottles stand safely.
Quick answer
The indentation at the bottom of a wine bottle is called a punt. When bottles were hand-blown, glassblowers pushed the seam inward to stop a sharp point of glass from forming on the base — a punt let the bottle stand flat and safely. Modern machines don't have that problem, so today the punt mainly adds structural strength to sparkling wine bottles (which hold serious pressure), helps trap sediment away from the pour, and gives you a natural thumb grip when serving. Deep punt does not mean better wine. It's mostly tradition.
A deep punt is not a quality indicator. Some manufacturers use exaggerated punts purely to make bottles look more impressive.

What it's called
A punt
Original reason
Glassblowing seam fix
Still useful for
Sparkling wine pressure
Quality signal?
No — it's a myth
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