Pewter is an alloy made mainly of tin. It used to contain lead, so an antique pewter flask may not be a good idea to use. New Pewter does not contain lead. Pewter can also react with anything that is acidic giving the beverage a metallic taste. It also oxidizes giving it a tarnished look. Stainless steel does not oxidize, and thus will not react with acids giving a visual change in the metal, nor an off-flavor. It is also lighter.
I suggest Stainless steel for a flask. In days of old stainless was not available so pewter was used. Stainless is cheaper and will offer better flavors with acidic beverages.
Yes. They can also be dangerous in an old pewter flask as pewter was once made with lead. Steel and glass are the best materials for a flask.
No, an oven being stainless steel does not make it work better than a non stainless steel version.
stainless steel
Stainless steel
A flask is typically made of stainless steel or glass. Stainless steel flasks are durable and long-lasting, while glass flasks provide an elegant look and do not impart any flavors to the liquid stored inside.
Potable items that cannot be stored in stainless steel: End of list.
The better conductor is stainless steel.
stainless is better.
Stainless steel is a popular material for thermos flasks because it is durable, has good insulating properties, and is easy to clean. Vacuum-insulated stainless steel thermos flasks can keep liquids hot or cold for long periods of time.
Stainless steel is stronger and retards rust unlike iron
A thermos flask is made of steel because steel is a good insulator, which helps maintain the temperature of the liquid inside the flask for longer periods. Steel is also durable and easy to clean, making it a practical material for use in thermos flasks.
Vacuum insulated stainless steel bottles like one from Hydro Flask [see related link "hydro flask" below] or Thermos [see related link "thermos" below] will keep them coldest.