Also referred to as the goblet in some traditions, or, more simply, the cup, the chalice represents the Goddess and the element of Water. It is a symbol of abundance and fertility, and has several purposes in Wiccan ritual, including offering libations to the deities and partaking in the cakes and ale ceremony. The chalice may hold water, wine or ale, depending on the ritual. It may also stand empty in some rituals, as a symbol of opening oneself to the abundance pouring forth from the spiritual plane. (Note: in any ritual calling for an alcoholic beverage, juice or herbal tea may be used as a substitute.)
Traditionally, the chalice is silver, a color (and metal) sacred to the Goddess. This type of chalice can be found at shops specializing in Wicca and/or other “NeoPagan” traditions. However, these can be expensive, and depending on the quality, potentially toxic to drink from. Wine in particular can corrode metal, so if you’re using a metal-plated chalice, use a separate libations cup for wine or other acidic beverages.
An elegant silver chalice can be lovely to work with, but it’s certainly not necessary. You can find something simpler and less expensive, or even dedicate a cup you already own for the purpose. It can be particularly powerful to use one that’s been in your family for a long time, as it will have a lot of loving vibrations stored up in it already. Goblet-shaped cups or short-stemmed wine glasses are nice, but anything that holds liquid will do. Wood, ceramic, metal or glass are appropriate materials. Plastic, on the other hand, is not recommended, as it is not an Earth-sourced material.
No matter what vessel you choose as your chalice, be sure to keep it reserved solely for ritual purposes. Don’t toss it in the dishwasher with all of your other cups. Wash it by hand, separately, and keep it with your other ritual tools. This way it will consistently hold the magical energy you have charged it with.
Want to put this into practice? My free spell book is a good place to begin.