Here's the derelict mine walks I can think of.
Devon MineThis is the best mine site I've bushwalked to. I expect the access has changed since Nic Haygarth wrote "On the Road to Cradle." His description starts on
a 4WD track that is now a brand-new side-road labelled "Cethana" heading east from Daisy Dell. (A new logging road I suspect.) The walk is quite long (but possibly shortened due to the new road) and it descends deep into the Dove River gorge. At the end of the track is a derelict hut called the "Hotel Hilton Hell Hole" (must have been classy in its day) and a flying fox over the river to the mine on the other side (pictured below). In the main addit, there are tramway remains and a very impressive shaft head frame (pictured above). EXTREME CARE should be taken. Just before you reach the headframe, there is another water filled open shaft which is very difficult to see. We measured the main shaft to be over 30 metres deep which takes it well below river level. Given the mine's location, I expect the Dove River flows directly into the adit at times.
Pelion Wolfram MineMy first trip to Mt Ossa started from here in 1983. This track made for a very short walk in to Pelion Plains. I can remember at least 2 gated adits in the
hillside. Two wheel drive access was fine as mining had only recently stopped and the road was in good condition. In 1994 I rode my pushbike in to the Wolfram Mine and the road was just passable as far as the damaged bridge just before the mine. When we arrived at the hut (below), I was surprised to find a heap of people there. Someone had broken their ankle and had been carried (shouldered) this far to wait for a Parks 4WD to pick them up. Perhaps this was one of the last vehicles to go all the way in.

In 2004, a colleague mountain biked in with a group of quad bikes. The road had deteriorated to the point where she was able to keep pace with the quad bikes as they had to spend a lot of time negotiating obstacles.
I still hope I can return to Patons Road as I would like to find the buttresses of Sloanes Bridge and perhaps find the Razorback Track up to the Commonwealth Creek Mines (see below).
Pelion Copper MinesLocated just down stream from the Old Pelion Hut. Not much to look at. I like mines with a good explorable adit and/or shafts.
DPA MineAs mentioned above, this is over the western flank of Black Bluff. I did this by pushbike so I also can't offer much help with walking times. It's a good
one to explore as you can enter the adit for a certain way and there are remains of the tramway that was used to cart ore to the surface. I tried to follow
the road down the valley beyond the mine as the map showed it continuing through to Middlesex. However, it was completely overgrown by button grass. I was sick of carrying my bike so I returned to Smiths Plains the way I came.
Lake WillThere's evidence of surface mining on the Lake Will Track only a few metres from the Overland Track. Nothing exciting though.
Commonwealth Creek MinesI read about these mines in another Nic Hargarth book about the history of the Mersey-Forth high country. I went dangerously close to these mines on a walk to the Hydro Hut when we visited Razorback Falls but we did not go out of our way enough to fossick. I've since heard that some equipment and water race remains can be found if you're keen enough. We were fascinated to find a large log with huge square metal pegs in it close to Lake McRae. You can read about my
Hydro Hut expedition here. As the crow flies, the Hydro Hut is close to the Wolfram Mine, but 700 metres higher.
Mt OssaThe track up to the saddle between Ossa Thetis passes by a small coal mine adit high on Ossa's NW flank. While there's not much to look at, I was fascinated that someone would be keen enough to mine way up there. I've since learned that Ewart's Track from Pelion through the Wallace and Murchison River valleys passed over this saddle so perhaps this mine dates from when this was a thoroughfare of sorts.
Dolcoath Hill MinesThis is another "On the Road to Cradle" walk from Nic Hargarth's book. This one didn't inspire me much. All the mines were alluvial sluicing so there's not
much to look at unless you are into gem stones in which case, I believe this is one of the best fossicking spots in the state. The highlight for me on this
walk was a derelict hut with a couch on the veranda facing a view to Cradle Mountain past the HV powerlines from the Pieman Scheme.
Thorsby's TunnelA good one to take the children to. A short walk along the track from Ferndene, this adit is long enough to make it fairly dark without the torch and
there's a gate to protect the vertical shaft at the end.
Round Mountain MineThis was just 2 wheel drivable when I was last there about 5 years ago but some of the ruts were over 1 metre deep so this area may have now become the exclusive domain of bushwalkers or mountain bike riders. The main adit is where the main road from Staverton to Lorinna used to cross Machinery Creek before the Hydro Roads were constructed. It is a large gaping hole in the mountainside from which deep slimy water emanates which discouraged me from exploring too far beyond the entrance. Apparently my grandfather-in-law used to work at this mine.
Jane River GoldfieldSpeaking of my grandfather-in-law, he is credited with cutting the original Jane River Track which now forms the first part of the Frenchmans Cap Track over the infamous 'Sodden Lodden.' The Jane River gold fields is a derelict mining area I would love to visit because of Mrs TasTrekker's family connection. However, the lack of bridge over the Franklin at the 'new' Jane River Track has discouraged me from doing so. Maybe one day! I have read about groups using 'The Jane' as access to reach Algonkian Mountain and the POWs. I would love to hear from anyone who has been there.