Thanks. I found this reference to the GRIM here but I don't see anything about incorruptible.
289. Among the requisites for the celebration of Mass, the sacred vessels hold a place of honor, especially the chalice and paten, which are used in presenting, consecrating, and receiving the bread and wine.290. Vessels should be made from materials that are solid and that in the particular region are regarded as noble. The conference of bishops will be the judge in this matter. But preference is to be given to materials that do not break easily or become unusable.
291. Chalices and other vessels that serve as receptacles for the blood of the Lord are to have a cup of nonabsorbent material. The base may be of any other solid and worthy material.
292. Vessels that serve as receptacles for the Eucharistic bread, such as a paten, ciborium, pyx, monstrance, etc., may be made of other materials that are prized in the region, for example, ebony or other hard woods, as long as they are suited to sacred use.
293. For the consecration of hosts one rather large paten may properly be used; on it is placed the bread for the priest as well as for the ministers and the faithful.
294. Vessels made from metal should ordinarily be gilded on the inside if the metal is one that rusts; gilding is not necessary if the metal is more precious than gold and does not rust.
In my mind, nonabsorbent and gilded are not the same as incorruptible.
Also, the original point was to deny "using corruptible metals, glass or ceramic for the sacred vessels, including the chalice". The extra emphasis on including the chalice seems to mean that the other vessels are included in this part of the instruction.
Well, unless the upcoming liturgical document states otherwise, the above instructions from the GIRM have been interpreted here in the United States to allow the use of crystal and glass cups for the Precious Blood.