Gary, The gold plating solution that comes with our gold finger repair kit contains the gold suspended in cyanide, and is dark purple in color. If this same type of solution is used at the fabricator and was not cleaned completely, it may be bleeding out under elevated temperature. Not the scientific answer, but something to investigate. Mike McMonagle -----Original Message----- From: Gary Camac [mailto:[log in to unmask]] Sent: Monday, August 28, 2000 1:45 PM To: [log in to unmask] Subject: [TN] Staining on edge connector << File: Card for Gary Camac >> Good morning all, I have come across something I have never seen before and thought it would be a good idea to see what my panel of experts have to say. I have some assemblies that are showing a purple stain in the laminate around the gold contacts of a board edge connector. Under the microscope, I see no sign of anything on the laminate on the boards from stock. I took a sample of the stock boards and ran them, unpopulated, through the reflow oven and - lo and behold - I've got a stain. The stain seems to be in the epoxy. A little light scratching with a knife blade takes off something purple. Any ideas as to what I am looking at? Gary Camac ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################