How very interesting about the oil. I got my MFA in glassblowing in 1964 and in all these years of following glass, I never knew that. But it makes perfect sense. And if it is a natural oil, those double bonds are going to oxidize and set up the oil over time. The metals in the glass will even catalyze that reaction. However, the surface schmutz tested alkaline. That argues more for leaching of the glass from humidity and air pollution. And being a chandelier, you certainly want to use a lead test on it before you clean it. Lead and lead compounds also skin-absorb -- a fact that somehow doesn't get into the literature much. Absorption through the skin now is known to be a significant additional route of entry in the lead industries. Do let us all know what you find out. It's so interesting. Monona Rossol
------Original Message------ This may or may not be pertinent to the greasy material on the chandelier. A few years ago in classes at the Corning Studio, I learned that many contemporary glassworkers apply an oil of some kind to their works as a final fabrication step. The oil hides tiny imperfections. Of course over time the oils oxidize, creating a foggy surface; and the sticky surfaces hold dust. Elsewhere, an objects conservator told me that she had great difficulty trying to remove such an oil from a Lino Tagliapietra piece. Christine A Smith6044 Old Telegraph RoadAlexandria, Virginia [email protected] <[email protected]> Reply to Sender : https://community.culturalheritage.org/eGroups/PostReply/?GroupId=481&SenderKey=6ea82495-27fc-43b2-804c-b5004e98b727&MID=9021&MDATE=756%253e465467&UserKey=d16eaa87-0f69-494b-9f2f-303dbc1222e1&sKey=fab9aa4f27a04c5d876e Reply to Discussion : https://community.culturalheritage.org/eGroups/PostReply/?GroupId=481&MID=9021&MDATE=756%253e465467&UserKey=d16eaa87-0f69-494b-9f2f-303dbc1222e1&sKey=fab9aa4f27a04c5d876e You are subscribed to "Global Conservation Forum (ConsDistList)" as [email protected]. To change your subscriptions, go to http://community.culturalheritage.org/preferences?section=Subscriptions&MDATE=756%253e465467&UserKey=d16eaa87-0f69-494b-9f2f-303dbc1222e1&sKey=fab9aa4f27a04c5d876e. To unsubscribe from this community discussion, go to http://community.culturalheritage.org/HigherLogic/eGroups/Unsubscribe.aspx?UserKey=d16eaa87-0f69-494b-9f2f-303dbc1222e1&sKey=fab9aa4f27a04c5d876e&GroupKey=757a8f16-505f-4323-8e74-e376757aa9f7.
