"why does she have it listed as aluminum?"

Because in bikes, many ebay sellers have no clue what they have exactly. My favorite was a Peugeot UO10 with Carbolite 103 steel tubing; it was listed as "carbon fiber" under frame material. Another one was a seller with an early PX10 who apparently got besieged with emails on a scale they had hitherto belived impossible. They had some interesting revisions on their auction...