What it is, and why it behaves this way
Beta titanium is a class of titanium alloys whose composition and processing produce useful mechanical properties. Springiness in a temple also depends on its thickness, shape and connections.
Weight in context
Fine sections can keep weight down; the beta label alone cannot predict total weight.
Flexibility & adjustment
Can provide elastic recovery within its limits. Excessive bending can still deform or break it.
What to check when trying on
Compare grip, not just springiness. Strong spring action can still feel tight.
Care & limitations
Adjustment must suit the design. Twisting a temple into a loop is not a useful care or quality test.
Put it into practice
Example: two beta-titanium temples of different thickness can press differently against the same head.
A common assumption to check
Beta titanium is neither pure titanium nor a synonym for nickel-titanium memory alloy.
Sources & scope
Page updated; sources checked: