Question: Whose helmet is it discovered in 1939 which is well preserved and together with the Coppergate Helmet?

Context:
Cretaceous Mongolia
Cretaceous Mongolia is one of the strangest and best preserved of all Mesozoic ecosystems.
 The shifting sand of what was, even then, the Gobi Desert have ensured that fossils of the animals that lived there can be found in exactly the position in which they were buried, with most of the bones together.
 The most notable fossil is the very well preserved remains of a "Velociraptor", locked in combat with a "Protoceratops", a small ceratopsian.
The Great Psalms Scroll
The Great Psalms Scroll, also referred to as 11Q5, is the most substantial and well preserved Dead Sea Scrolls Psalms manuscript of the thirty-seven discovered in the Qumran caves, six of which were discovered in Cave 11.
 It was discovered in February of the year 1956, ten years after the initial discovery of the scrolls.
 It was purchased by The Palestine Archaeological Museum located in Jerusalem and first unrolled in November 1961.
 Four fragments of this scroll were later purchased by the same museum.
 The scroll’s physical make up is that of dark yellow animal hide and is a little less than 1 mm thick.
 The primary body of the manuscript consists of “5 sheets of leather, still sewn together”, and is 4.253 meters in length.
 It is estimated to have been copied anywhere from 30-50 C.E., and is written in Biblical style Hebrew.
 When rolled out, it forms a slight arc, and the top part is clean and well kept, while the bottom is decomposing significantly.
 It was first edited and published by James A. Sanders in 1965, with a second volume also published by Sanders two years later with a wider and more general audience in mind.
 The full scroll is published in the Leon Levy Dead Sea Scrolls Digital Library.
Shorwell helmet
The Shorwell helmet is an Anglo-Saxon spangenhelm type helmet found near Shorwell on the Isle of Wight in 2006.
 Together with those from Benty Grange, Sutton Hoo, Coppergate, Wollaston, and Staffordshire, it is one of only six known Anglo-Saxon helmets.
Varugad
The hill rises about 250 feet above the level of the plateau, which itself constitutes the summit of the Mahadev range at this point.
 The cone with the walls on it is seen from a great distance and appears very small indeed.
 But on near approach it is seen to be but the inner citadel of a place of considerable size and strength for the times in which it was built.
 On the south-west the outer wall or enceinte is entered by a rude gateway of a single pointed arch about eight feet high and five feet broad.
 As usual there is a curtain of solid masonry inside.
 The gate lies about 150 yards east of the edge of the plateau, which there terminates in an almost unbroken vertical precipice of several hundred feet in height and receding in a north-easterly direction.
 No wall was built along about three hundred yards of this part which is absolutely unscalable, but for the rest of the way the walling is continued along the edge of the cliff in a north-east direction for about another three hundred yards.
 Here it turns still following the cliff to the south-east for another seven hundred yards, and then gradually rounds to the westward covering four hundred and fifty yards more till it meets the gateway.
 But for the break of the inaccessible precipice this outer wall would form a nearly equilateral triangle with the corners rounded off, the side being of some six hundred and fifty yards.
 Facing nearly north, about fifty yards from the north-east angle, is a gateway with a couple of curtains in solid masonry.
 This entrance is cut in the sides of the cliff about twenty feet below the top which is reached by some dozen steps.
 It consisted as usual of a pointed arch, the top fallen in, about ten feet high by five broad.
 It leads out to the path down to Girvi, a village in the plains below and it probably formed the communication with Phaltan.
 This road winds down the face of the range for some five hundred feet till it hits the shoulder of a spur which it then follows to the base.
 The walling on the south side, from the edge of the cliff to some hundred yards east of the southern gate, is not more than a couple of feet in thickness and consists of all-fitting stones unmortared.
 The rest is massive and well mortared and still fairly preserved.
 The average height is from seven to ten feet.
 In the south-east angle is a rude temple of Bhairavnath and a few houses with the remains of Man y more.
 On the right side of the southern gate is a well preserved stone pond about thirty yards square with steps leading down to it.
 Next to and on the north of Bhairavnath's temple is another pond.
 The way up to the fort proper or upper and lower citadels is from the north side.
 The path up the hill side, which is steep but with grass and soil left in Man y places, is almost destroyed.
 About 150 feet up is the outer citadel built on a sort of shoulder of the hill and facing almost due west.
 It contains two massive bastions of excellent masonry looking north-west and south-west so that guns planted on them could comMan d respectively the north and south gateways.
 This citadel was connected with the main wall by a cross wall running across the whole breadth of the fort from east to west.
 Its entrance lies close below that to the upper citadel.
 A masonry curtain projects so as to hide the arch itself, which is not more than seven feet high by three broad, and has to be entered from due east.
 On the south side the walls are carried right up to the scarp of the upper citadel and are some ten feet high, so that to take the lower citadel in rear or flank must have been difficult.
 The upper citadel is above a vertical scarp some thirty feet high.
 The entrance to it lies some thirty feet above that to the lower citadel, and is cut in the rock about eight feet wide.
 There is a gateway of a pointed arch with the top fallen in and twenty odd steps leading up to it and ten more cut out of the rock, and winding up past the inside curtain on to the top.
 The walls of this upper citadel are still in tolerable preservation.
 They were originally about ten feet high and built of fair masonry.
 There is a large turret on the south-west corner, evidently meant to comMan d the southern gate.
 About ten yards to the east of this turret is a new looking building which was the headquarters or sadar.
 Immediately east of this and below it is a great pit about thirty feet square and equally deep roughly cut in the rock and said by the people to be a dungeon.
 Next to it on the south is a small pond evenly cut and lined with mortar used for storing water.
 There are some remains of sepoys' houses, and, near the turret, a small stone wheel said to belong to a gun.
 The outer walls east of the gates have bastions at every turn of the cliffs, and the masonry here is particularly strong and well preserved.
 It would appear that attacks were dreaded chiefly from the plain below.
 The assailants could either come up the spur towards the north entrance or they might attempt the spurs on the other side of the eastern ravine and attack the southern gateway.
 Hence apparently the reason for strengthening the walls of the enceinte on this side.
 After passing the southern gateway the assailants would be commanded Maan, Maharashtra from the lower citadel.
 They Would then be encountered by the cross wall.
 If that obstacle was overcome the besieged would run round the east side and into the two citadels.
 The appearance from the fort of the plain in the north is most formidable.
 The Panvan plateau completely commands Maan, Maharashtra and almost overhangs it.
 The fort is believed to have been built by Shivaji to resist the Moghals whose attacks he must have dreaded from the plain below.
 The Karkhanis or Superintendent of the fort was a Prabhu.
 The fort garrison consisted of 200 Ramoshis, Mahars, and other hereditary Gadkaris besides sepoys.
 It was surrendered in 1818 to Vitthal Pant Phadnis of the Raja of Satara left in charge of the town.
 He detached 200 men to take possession, being part of a force then raised to protect the town from the enterprizes of Bajirav's garrisons then in the neighbourhood.
 [Elphinstone in Pendhari and Maratha War Papers, 245.]
Coppergate Helmet
The Coppergate Helmet (also known as the York Helmet) is an eighth-century Anglo-Saxon helmet found in York.
 It is remarkably well preserved and, together with the Benty Grange, Pioneer, Shorwell, Sutton Hoo, and Staffordshire helmets, is one of only six Anglo-Saxon helmets discovered to date.
Pioneer Helmet
The Pioneer Helmet (also known as Wollaston Helmet or Northamptonshire Helmet) is a 7th-century Anglo-Saxon boar-crested helm found by archaeologists from Northamptonshire Archaeology at a quarry site operated by Pioneer Aggregates.
 This helmet is very similar in its basic design to the Coppergate Helmet, although it is much larger, and was likely to have had two cheek plates (of which only one remained) and a nasal (which was bent inwards at the time of deposition to render the piece unwearable).
 A simple iron boar crest adorns the top of this helmet associating it with the Benty Grange helmet and the Guilden Morden boar from the same period, and descriptions in the poem Beowulf.
 The helmet accompanied the burial of a young male, possibly laid on a bed with a pattern welded sword, small knife, hanging bowl, three iron buckles and a copper alloy clothes hook.
Joseph-Martin Cabirol
Joseph-Martin Cabirol was a French man.
 In 1855 he patented a new model of standard diving dress in Paris, mainly from Augustus Siebe's designs, and afterwards he made them.
 The suit is made out of rubberized canvas.
 The helmet, for the first time, includes a hand-controlled tap that the diver uses to evacuate his exhaled air.
 The tap includes a safety valve which stops water from entering the helmet.
 Until 1855 diving helmets were equipped with only three circular windows (front, left and right sides).
 Cabirol's helmet introduced the later well known fourth window, in the upper front part of the helmet and letting the diver watch above him.
 Having been presented to the "Exposition Universelle" in Paris Cabirol's diving dress won the silver medal.
 This original diving dress and helmet are now preserved at the "Conservatoire National des Arts et Métiers" in Paris.
Sutton Hoo helmet
The Sutton Hoo helmet is a decorated Anglo-Saxon helmet discovered during the 1939 excavation of the Sutton Hoo ship burial.
 It was buried around 625 and is widely believed to have been the helmet of King Rædwald of East Anglia, and its elaborate decoration may have given it a secondary function akin to a crown.
 The helmet is "the most iconic object" from "one of the most spectacular archaeological discoveries ever made," and one of the most important Anglo-Saxon artefacts ever found.
 Its visage features eyebrows, nose, and moustache, creating the image of a man joined by a dragon's head to become a soaring dragon with outstretched wings.
 It has become a symbol of the Dark Ages and also "of Archaeology in general."
 It was excavated as hundreds of rusted fragments, and was first displayed following an initial reconstruction in 1945–46, and then in its present form after a second reconstruction in 1970–71.
Microleter
Microleter is an extinct genus of parareptile which existed in Oklahoma during the Early Permian period.
 It was first named by paleontologists Linda A. Tsuji, Johannes Muller, and Robert R. Reisz in 2010.
 The type species is "Microleter mckinzieorum".
 A very well preserved skull and lower jaw is the only known specimen.
 It was found from the Early Permian (early Kungurian stage) fissure-fill deposits near Richards Spur in Comanche County, often referred to as the Fort Sill locality.
 The Fort Sill locality has yielded many other well preserved tetrapod fossils, including those of other parareptiles such as "Bolosaurus", "Colobomycter", and "Delorhynchus".
Staffordshire helmet
The Staffordshire helmet is an Anglo-Saxon helmet discovered in 2009 as part of the Staffordshire Hoard.
 It is part of the largest discovery of contemporary gold and silver metalwork in Britain, comprising nearly 4,000 pieces.
 Following those found at Benty Grange, Sutton Hoo, Coppergate, Wollaston, and Shorwell, it is only the sixth known Anglo-Saxon helmet.

Answer: is widely believed to have been the helmet of King Rædwald of East Anglia