A copper bowl is not just a bit of useless fanciness for the kitchen. The real reason is egg whites.
Copper strengthens the proteins of egg whites for more lift and stability.
Remember to use a big balloon wisk since this is about getting air into those whites. It will also be good for making Zabaiogne, the Italian custard with Marsala wine, sugar, and eggs. Don't cook anything else in copper since the reactions with some chemicals can be toxic. Clean and polish the bowl before and after usage with a mixture of vinegar and salt - rinse with hot water and dry thoroughly.