I'd say it's probably wendtii/becketti/undulata, but i could be something rather different .... The reason i think that it's one of them is that they are the most common crypts that tend to have lanceolate leaves, at least where i come from.
But to get a sure ID you HAVE to flower them, it's the only way. And even if they flower, you will be confused, since comparing flowers isn't necesarilly easy at all. But that's the way you have to go to get a sure ID, if you can't just ask your friend.
The best way to ID any given species is through DNA analysis, although this is not so frequently done by many people. Most simply don't have the access. Flowering will not tell you accurately, since many plants(most organisms, for that matter)share nearly identical phenotypes; it is in their genotypes that hold the key to their identification.
Furthermore, over the years even wild type Crypts have cross-bred for who knows how long or how much. Any particular Crypt we have is likely a result of cross-bred specimen. Unless you can pin-point its P1, F1, F2,....basically its geneology, it is too hard to be able to narrow down to the species level, without molecular analysis.
Unfortunately the friend who it came from is no longer with us.
I did find something in one of her galleries about a Crypt that may be this one.
She called it a Volunteer Crypt, and here was what she had to say about it:
"Here's one of my most interesting crypts--it's growing in my 55 gallon, and I have no idea where it came from. I've never had crypts on this side of the tank. There are many bronze petchii on the other end, but they're over two feet away, and I don't think this is the same variety, it looks nothing like the new petchii plants do when they emerge. Two little green leaves popped out of the substrate about 2 months ago, and I thought it was a piece of java fern at first. It looks like it's some sort of wendtii, but I guess I'll find out eventually. The newest leaves are coming out bronze now, and the biggest are about two inches long; several others are starting to emerge around it, also. You just gotta love crypts, they're always full of surprises!"
I guess even if it isn't ID'able, I'll just enjoy it for it's beauty in the tank.