If you're interested to know more about this blade, I think it may be worth seeing if this is a Tuban style keris. It has a low gandhik and shallow blumbangan, which are features that might support this classification.
One way of assessing this is by looking straight down onto the flat face of the gonjo, like shown here:
http://www.vikingsword.com/vb/showpo...2&postcount=23
This post will give you an idea of what to look for:
http://www.vikingsword.com/vb/showpo...2&postcount=17
Of course these cues are visual only. My understanding is that opinions about a keris' classification can change when it is in the hand of someone experienced.