I've got a clear calfskin head on one of my banjos. It seems much more susceptible to humidity than the white head. I also have one on my gourd banjo, it is thicker, and seems to do better, although I think that this is due to it being smaller.
Hey John, I think calfskin sounds good from the beginning, in other words, goatskin has to do its stretch then has its nice tone. Goatskin will stretch once. They sound similar to me, and I've installed hundreds, but mostly goat because most people want solid color. Also, from among my several different sources, the goatskins from Elderly's sound best. I don't know why or where they get them. I go there and pick through them. If you were to order one, I'd order two or three so you get the correct thickness.
There is a great account of the early days of banjo heads written by Albert Baur in the SSS Journal. He tells a funny story about the first banjo head he ever fitted. He also talks about getting how they got heads during the war (a story that is often repeated uncredited).
Then, as now, heads are subject to the whelms of fashion. Tastes changed from time to time based on looks and ideas that one style sounds better than another.
The transparent heads are typically associated with being slunk, coming from an unborn calf. Whether or not they actually are I don't know.
By the late 60s you typically see white opaque heads. Slunk and blotchy still exist enough in the 1880s and 90s to get mentioned, but by that time most of the heads were made by Rogers.
I'd think that early on you used what you could get, likely a thin drum head (or in the case of Frank B. Converse a stolen dog).
Historical evidence suggests that any of these would be correct (just not artificially aged). I like the look of opaque white, but I won't change one that sounds good and is not too terribly effected by humidity just for looks.
At one point it was in fashion to take it to a marblier and have it marbled. I've not seen photo evidence of this (it may just not be showing up) but that would be very cool!
Hi Joel, thanks for the information! Judging by your post (although it's early in the morning and I haven't had coffee, so I may have read this wrong), blotchy clear heads would be fashionably correct for an 1850s banjo. I'm not swapping out the head for looks... it's likely the original head, and is at least as old as 1875 according to the writing on it. In the past it broke in multiple places and was patched back together. Whoever did this did a good job, but it left the head rather fragile. It also has no length left so it cannot be tightened further, which it could use.