[Yeah, this would only appeal to the occasional geologist visitor.]
Having been involved with Geology for more than 35 years, there are a few minerals that I would like the experience of having "dug" myself or at least to have found them on a mine dump. Some of these I do own specimens of, having bought them or traded for them. But I would like the "wow" experience of having found at least a recognizable specimen, by my own hand.
In no specific order, they are:
1) Topaz - it has been reported from Graves Mt., GA and I have a mystery crystal from that locality that I would like for someone to verify, yes or no.
2) Garnets - with good crystal faces, at least 3/8 inch in diameter.
3) Biotite mica - some thin "books", at least 2 inches by 2 inches square.
4) Millerite - a fibrous nickel sulfide, found in small geodes near Halls Gap, KY.
5) Zircon - a decent crystal, at least 3/8 inch on any particular side.
6) Brookite - a titanium dioxide mineral from Magnet Cove, AR.
7) Wulfenite - have a number of purchased crystal specimens, would like to find one.
8) Apatite - a decent, recognizable crystal. I think I have some small apatite crystals in marble from Tate, GA and in some pegmatite material from Maine, but they are all in matrix.
9) Lazulite - some decent crystals from Graves Mt., GA. I have some weathered and broken specimens, but no decent ones.
10) Spodumene - a lithium silicate, I have been to one locality in NC, but didn't find any.
11) Selenite (gypsum) - from Jet, OK, for instance. I have found gypsum in several localities, but not any decent crystals.
12) Barite - crystals from Cartersville, GA. I have barite crystals collected from Graves Mt., and the Bishop Cap Hills in southern New Mexico. But I have missed field trip opportunities for the Cartersville area.
13) Vivianite - a nickel phosphate. Some small masses of vivianite have been found inside of fossil oyster shells on the Georgia Coastal Plain, near Providence Canyons. The vivianite was deposited inside the shells by groundwater action.
14) Talc - just some decent, light colored masses of the mineral, not the metamorphic rock (which I already have).
15) Epidote - just a decent sized, 1/2 inch length or longer crystal. I have smaller crystals, but not big enough for non-collectors to appreciate.