GIRM 326. In choosing materials for sacred furnishings, besides those which are traditional, others are admissible that, according to the mentality of our own age, are considered to be noble and are durable, and well suited for sacred use. In the Dioceses of the United States of America these materials may include wood, stone, or metal which are solid and appropriate to the purpose for which they are employed.
III. Sacred Vessels
Among the requisites for the celebration of Mass, the sacred vessels are held in special honor, and among these especially the chalice and paten, in which the bread and wine are offered and consecrated and from which they are consumed.
Sacred vessels should be made from precious metal. If they are made from metal that rusts or from a metal less precious than gold, they should generally be gilded on the inside.
In the Dioceses of the United States of America, sacred vessels may also be made from other solid materials which in the common estimation in each region are considered precious or noble, for example, ebony or other harder woods, provided that such materials are suitable for sacred use. In this case, preference is always to be given to materials that do not easily break or deteriorate. This applies to all vessels that are intended to hold the hosts, such as the paten, the ciborium, the pyx, the monstrance, and others of this kind.
As regards chalices and other vessels that are intended to serve as receptacles for the Blood of the Lord, they are to have a bowl of material that does not absorb liquids. The base, on the other hand, may be made of other solid and worthy materials.
[117.] Sacred vessels for containing the Body and Blood of the Lord must be made in strict conformity with the norms of tradition and of the liturgical books. The Bishops’ Conferences have the faculty to decide whether it is appropriate, once their decisions have been given the recognitio by the Apostolic See, for sacred vessels to be made of other solid materials as well. It is strictly required, however, that such materials be truly noble in the common estimation within a given region, so that honour will be given to the Lord by their use, and all risk of diminishing the doctrine of the Real Presence of Christ in the Eucharistic species in the eyes of the faithful will be avoided. Reprobated, therefore, is any practice of using for the celebration of Mass common vessels, or others lacking in quality, or devoid of all artistic merit or which are mere containers, as also other vessels made from glass, earthenware, clay, or other materials that break easily. This norm is to be applied even as regards metals and other materials that easily rust or deteriorate.