The Wimberry Colliery was situated on Old Furnace Level gale, originally granted to Aaron Hale and Edward Baldwin, both Free Miners, who assigned their interest on lease for 500 years to David Mushet in October 1821.  The 1841 Coal Awards, following Sopwith's survey, confirmed this.  In 1847 David Mushet died and his interests passed to two of his sons, William and Robert.  In 1855 they applied to the Crown for permission to sink a pit and establish a colliery at Old Furnace, but this was suspended the following year due to doubts about the position of the coal seam.
 
GRO D192/4
17 April 1857  Auction at the Bear Inn, Newnham; 2/9 of Bixslade, Howler Slade & Old Furnace Collieries, sold by order of High Court of Chancery.
Also a freehold Brickyard, cottage and four acres.
In Chancery between Crawshay Bailey, Thomas Greatrex & William Williams; and David Mushet, Samuel Martin, Thomas Basket, Henry Dunkerton Martin, John Porter, James Herbert, John Walkinshaw, Charles Morgan, John McArthur and George Baker.
And between David Mushet and Charles Frederick Cliffe (since deceased), George Roberts, William Mushet and Robert Mushet.

Old Furnace partially opened by a level in Howlers Slade.  Four openings, of which three in use, connected to Severn & Wye.  The Howlers Slade & Old Furnace Collieries adjoin the Turn Pike road from Coleford to Newnham.
Bixslade & Howlers Slade galed to the Coleford High Delf.  Old Furnace to the Coleford High Delf.
Unexploited areas in Bixslade and Howlers Slade in Coleford High Delf 118 acres at death of Mr. Mushet in 1847.  This calculation made in 1853 by Mr. Marcus Scott, an engineer employed by the executors to survey the property.  Old Furnace 198 acres.
Collieries have been worked ever since Mr. Mushets death except that Howlers Slade Deep Engine was not then reached but it was reached by a level cutting.
Coal from Michaelmas 1854 to Michaelmas 1856 is 85,412 tons 12 cwt.
Bixslade Level under lease dated 13 June 1817 from James Teague to late Mr. Mushet for 500 years at £1 1s. per annum.  Howlers Slade & Old Furnace Level lease dated 1 October 1821 from Aaron Hale and Edward Baldwin to Edward Protheroe for 500 years at 5s. per annum.
Valuable plant: underground trams, plates,air trunks, sleepers, pumps, bellows, anvils, underground plates, ditto on the tips, engine 10 horse power.
A Freehold brickyard about two miles from collieries.  Grinding Mill, Kiln & Buildings for making fire bricks, capable, when in repair, of producing 300,000 per annum.

In 1864 the lease, possibly even ownership of the gale rights, passed to Trotter, Thomas & Co., the partners in which were John Trotter, Theophilus Trotter, James Thomas, William Whitworth, Nathan Atherton, Joseph Priestly and William Crowdry.  This company evidently began work at Wimberry as, in 1867, they wrote to the Severn & Wye stating that output from Wimberry Pit could be increased if it was served by a railway rather than a tramroad.  This facility was eventually gained and in 1874 they further extended the siding.
On 28th July 1871 during a strike at the colliery a P.C. Blackwell was on duty at the pit when on arrival at 7.30 pm he found that the pumping engine was stopped and was informed that the engineman, one Thomas Rudge, had found something wrong with the pumping gear and had gone to investigate.  Early the next morning the engineman was found crushed to death underneath a large quadrant beam.  It was recommended at the ensueing inquest that the engineman should not be left alone on night duty.
By 1885 the company was in financial difficulties and the following year were unable to pay the dead rent due to the Crown.
Output in 1888 was recorded as 517 tons.
A report in 1890 shows the Old Furnace Level was disused and that the shafts were fenced round.  In 1891 Old Furnace and another level held by the company, Vallets Level, were forfeited to the Crown for non-payment of the dead rent.
In 1891 Old Furnace Level was re-granted to a committee of 160 Free Miners, headed by Benjamin Cooper, and they formed the Wimberry Colliery Co.. An interesting point about the grant was that for the first time since the passing of the 1838 Mines Act lots had to be drawn to decide who the gale was to be granted to, normally the Free Miners decided amongst themselves. A newspaper report about the new company explains why the colliery had previously failed.  It states that flooding was the cause of closure and, as with both the later Cannop Colliery and  with Speech House Hill, water was always the greatest problem in this part of the coalfield. A Dean Forest Mercury report on the 20 October 1893 states that the flooded, disused colliery in Wimberry Bottom was about to be re-started.
Output in 1894 had risen to 2,904 tons.
13 August 1897 Double shift started, 50 more hands.
The water problem came to a head again at Wimberry in December 1897 when, on the 20th., a heading broke into some flooded old workings.  Thirty-four men and boys managed to escape the influx and reach safety up the main shaft but five men and a boy were cut off.  The colliery manager, Mr. J. J. Joynes, immediately called for volunteers and with three others, Philip Watson, Samuel Mansfield and the under-manager John Davies, went underground to effect a rescue.  This was completed after two hours and for his part in it Joynes was awarded the Royal Humane Society's silver medal, with bronze medals awarded to the other three.

24 December 1897 DFM Report of flooding.
22 July 1898 N. J. Trotter listed as Managing Director, Wimberry Colliery.
5 August 1898 Rpt. of medal presentation after Wimberry flooding.

In April 1900 it was reported that the workings in the Coleford High Delf seam had reached the barrier with the Old Engine and Worral Hill Level gales.  The owners of Wimberry asked permission from the Crown to work the coal in the barrier, having previously obtained the consent of the owners of the adjacent gales.  The Crown, however, refused permission for this. This effectivly meant that the colliery was virtually worked out, and the company started to work the 'pillars' back to pit bootom.  Pillars were blocks of coal left in place to support the roof and prevent too much pressure being exerted on the underground roadways. Obviously once all the workable coal had been extracted the pillars could be removed as supporting the roof was no longer of any consequence and the pillars provided quite a large amount of coal.  As well as the problem of running out of workable coal, the company was also in financial trouble.  In 1901 the debenture holders took control of the pit and were reported as endeavouring to dispose of it as a going concern.
From 8th July 1901 the colliery was leased to Amos W. Brown for a period of five years.  He purchased all the colliery plant including the siding at the end of the Wimberry Branch and the tramway linking it to the colliery.  In 1904 it was discovered that a license for the constuction of the sidings and tramway had never been obtained from the Crown.  One was promptly drawn up and signed, but only after Brown had attempted to gain the use of the siding for another of his interests further up the valley.  The Crown, presumably still vexed about all the rent money they had lost over the years, promptly refused permission.  In July 1904 Brown gave notice of his intention to cease pumping at Wimberry, but was informed that as he had not given notice of surrender the gale he must continue.
Following the 1904 Mines Act and the amalgamation of the deeper coal measures, steps were being made to work this area of the coalfield.  To this end a north country syndicate attempted to obtain Wimberry. The syndicate was led by Mr. M. Maclean and he offered £1,000, which was stated to be a fair price as the colliery was nearly worked out.  The Wimberry Colliery Co., however, would not sell out, obviously thinking that they would gain a higher price as the gale was wanted for to save the expense of sinking new shafts.  It was said to the Crown that 'here was a wealthy gentleman ready to commence but stopped by a few miserable and stubborn people'.  These were, of course, the 160 Free Miners,a nd it has to be said that £1,000 did not give each individual a very large return on his interest.  By 1906, however, Maclean had decided to sink new shafts elsewhere and thus the chance to sell Wimberry had gone.
In November 1907 the Wimberry Colliery Co. offered to sell out to Maclean and the Cannop Colliery Co. for £500, but all they were offered was £300!  It is not claer whether the concern was still being worked at this time but the offer was finally accepted following a certain amount of pressure from the Crown, and in 1908 the Old Furnace gale was amalgamated into the Western United gale and became part of Cannop Colliery.  The old Wimberry shaft was fitted up with a ventilating fan and engine house to supply air into the Cannop workings.
1908 Potts Mining Register
Amos W. Brown. Wimberry - Wimberry Colliery, Coleford.
N. J. Trotter, Secretary, Coleford.
Shipping ports; Sharpness, Newport, Lydney and Cardiff.
J. J. Joynes, manager.
18 employed below ground, 13 above.