A chalice is a vessel used to hold the wine during Mass. Most chalices are comprised of three parts: The cup, a central stem and a base. Originally, chalices were made of glass, but by the 9th century most of them were fabricated of precious metals. Today, chalices for Catholic use must be made of “non-absorbent material that is solid and worthy.” The inner part of the cup that comes in contact with the sacred species must be gold or gold-plated. The actual shape of the chalice is left to the imagination of the artist, but it must be reverent and approved by the Conference of Bishops of that region.