A few more rambling thoughts on “cold” stemware…….
We know that smaller things warm up quickly and larger object warm up more slowly. Specifically objects with larger thermal masses warm up more slowly. Usually, but not always, thermal mass correlates with object mass.
Additionally some materials are thermal insulators, meaning that heat moves slowly through the material (think Styrofoam cups). Some materials are thermal conductors (think copper frying pans). But restaurants and bars serve Martinis in glass, maybe crystal. We rarely have the option of asking for ‘good’ stem material.
To maximize the time of coldness, I want a Martini with a large thermal mass. But most bars will not give you a pint of Martini. They have one, maybe two, sizes of stems and they pour measured amounts of gin and vermouth. The only other variable is the stem itself. So make mine the largest most massive piece of glass, or lead crystal, available.