I have 2 guesses 1 is an old lincoln 7010. Lincoln use to have a dot/color system for rod identification, and I've saw and burned plenty of pink lookin 7010's. My second guess is that it could be a special composition rod designed and produced for a specific welding situation where unusuial alloys were to be joined. This is the less likely situation because if that is what it is the rods were most likely very expensive and not many made. I even bring this up because I've saw this situation one time in 20 years of welding. We were joining some extensions to the burners of a coal burning power plant boiler. The extensions were made of 316 stainless, but the original burners were made of somekind of patented "secret recipie" alloy and the rods to join the 2 metals had to be designed specificaly for this job.Those rods were like none I've ever saw again, they were army green colored flux, with grayish colored filler wire, the boxes only had Avesta Welding Porducts on the label and some numbers. Nothing like an AWS designation or anything that would give away there composition. And I remember they were obviously very expensive, because there were 2 of the engineers on the project helping us to actually fit-up the extensions and were crawling all over us for bending the rods to get back into corners and not burning them down to at least a 2" stub. One told me to stop bending them and I kindly stepped back and offered him my hood and stinger and asked him politely to show me another way to do it, of course he looked at me and looked at the joint I had and just shook his head and mumbled "well just do the best you can to not waste anymore than you have" to and walked away.