Broken Nipple

Posting in Bicycling Mechanics and Road Cycling forums

I have a road bike with Mavic Aksium wheelsets. I bought the bike new in 2009. Recently the rear wheel developed a pinging noise when going uphill or gaining speed. I decided to check the spoke tension. Without getting into too much detail let’s just say while I was tightening up one of the spoke nipples it broke in half. The round part that goes into the rim broke from the square part that you grip to tighten. Since the square part broke off my spoke tool is useless. I tried turning the spoke nipple with a pair of pliers but it won’t move. I have 3 bikes and enjoy doing work myself so I’m going to order the tools necessary to do wheel truing but I had a question about what I need to repair my wheel so I can start riding. I searched for hours and hours and I’m pretty sure the nipple needs to be brass at 16mm long but I don’t know how thick or what kind of spoke to order(carbone, ssc sl, crossmax st?)

What type of spoke nipple and spoke should I order so I can fix this?

Thanks.