The wide mule track, branched in several short variations, goes hardly up the slope looking for the best direction in a kind of skeleton field, that is, of rocky boulders of all sizes, from several meters to few centimetres, in total mix. The boulders have slightly rounded edges, and belong mainly to the species of rock coming from the walls overlying the Verra Plain, the serpentinites: a dark, bluish, and slippery rock. That is enough to merge this land to the moraine given by the ancient Verra glacier, which descend along all the entire valley. The larch wood has managed to grow on this poor soil, and nobody never tried to remove it to made grasslands or agriculture fields (except for tiny terracing, and in small area with alluvial deposits).

Here we are at the big rock hovering on the ridge overlooking the torrent. It is not clear how this big serpentinite boulder got there, but among the various curious things of this place there is a nice soapstone slab exposed under the boulder, on the upstream side. Several engravings appear on the slab, of which the most significant appear to be the cadastral limit on the right.
In Aosta Valley, the manufacturing of soapstone products (containers, stoves, furniture) is well proved, particularly starting from the VI century A.D. In Saint Jacques, large stockpiles of soapstone lathe waste attest a lively production of vessels. Quarried and laboratories are still to be identify with certainty.

The unmarked path, running along the flat torrent, and then climb a ridge, reveals incredible works of stone removal, terracing, and support for the conquest of few square meters of grassland. And, in fact, the stone removal here is a titanic work as the ridge is the right lateral moraine left by the ancient glacier of Verra, in fact a wall of stone. This wall of stone forces the Tsère torrent to flow suspended on the side of the valley in a corridor between the side and the moraine: it can only join the Evançon torrent down to Blanchard.
But the corridor with the torrent that flows half way up, on our left, is very welcoming: along its way there are fine grained deposits that occasionally spread out in more or less humid green clearings. On the wider green clearing, up on the passageway, stand out some big boulders with regular geometric shapes that make teenagers happy fancy bouldering.
You can get there by taking the first detour to the left, and crossing the Tsère torrent on two side by side trunks.

On the 8E path that rapid goes up towards the narrow, and lengthened valley of Tsère, we finally meet what matters, for a structural geologist: the outcropping rock. It appears in a scenographic way with a succession of high and smooth dihedrons of black rock, resulting from vertical cracks that mark the wall at regular distance. The black colour derives in part form alteration (manganese oxide?), but the rock is in any case dark because it is rich in iron, magnetite in particular, as you can see with a magnet. It is serpentinite (hydrated silicate of magnesium with magnetite), the same rock we have already found as glacial deposit in the mule track to Fièry, and as flap debris in Amena valley. The serpentinite comes from under the ocean floor, from the metamorphism of peridotite, which thewhole Earth's mantle is made of (the thick zone lying between the Erath's crust and core). As a matter of fact, we are starting a crossing of the ancient oceanic crust that was covering the alpine area in the Jurassic (150 millions of years ago), and which we find beautifully represented in the Cime Bianche valley.

On the Tsère plain, the view on mirror rock parade, closing the plain to the mountains, is stunning: smooth black walls, aligned, flat, and very tilted, which slip into the grass. Here again, with a magnet, we can verify the rocks are serpentinite, but in this case they provide us more information. Those walls are smooth as a consequence of a fracture with sinking of the rock mass that was originally together, a sudden sliding, and presumably as long as the the height of the walls themselves. Thus, where previously there was continuity of the rock a depression was created, then filled with pebbles and soil. This is the origin of the Tsère plain, but its age is quite uncertain. As a matter of fact its mirror surface it seems to be exposed to atmospheric agents only recently (after the deglaciation), but the fault could have occerred much earlier at weak depth.

The TMR (Mount Rose Tour) trail runs across the plain until it crosses the torrent, then passing in front of the black mirror, and climbs the ridge that delimitates the Tsère valley. Halfway up the hill, you walk on a strip of pale blue fragmented rocks. After some tests with lens, and magnet, we hardly recognize the Tsère serpentinite: these ones are laminated towards the top by metabasite that in the oceanic crust are at next higher level. We do not see metabasite outcrops yet, because are under detrital deposits, but we can recognizes some among the boulders spread on the grass. The magnet does not stick to these rocks.

Ocean floor are, and always have been, very active geologically speaking: plates are moving fast, magma bodies intrude in the oceanic crust or erupt on the seabed. From Alpe Varda on rocks reproduce, in their entirety, the chemical composition of those magmas: iron and magnesium silicates, with a part of an other silicates more sensible to heat (calcium, sodium, aluminium). But there still a issue: minerals are no longer the same. Between the ocean floor (150 millions of years ago), and the current mountains magma went through a spectacular sinking (45 millions of years ago) of the oceanic plate which metamorphosed the basaltic minerals in high pressure minerals. Due to the narrowing of the space between the continents, the oceanic plate subducted under the African continental plate reaching great depth (high pressure) the original magmatic minerals could not stand it. All we find nowadays in the ground is evidence of this passageway in depth. For this reason these rocks are no more called basalt or gabbros (magmatic rocks), but metabasite (metamorphic rocks).
The metabasite we find at this intermediate level are mainly rusty, and difficult to understand. Only in some place, for example on the top of grassy ridge in front of Alpe Varda, the fresh crack let distinguish small green crystals (onfacite), red crystals (garnet), and white crystals (zoisite?) coming directly from the bowels of the Earth (they form only over 60 km deep).

A straight slit, with vertical walls, runs along the slope exposing the rock. Mainly almost 10 meters large, and deep a bit less, it goes down slanting along the Palon of Tsère, comes in and then goes out from the Alpe Varda peat bog. On the path, we cross the straight with short descent, and with a short uphill, before merge on the left in the large path no. 6. It is a deep rift in the ground, with a frack and dislocation of the rocky mass that reveals the tension to which the Cime Bianche valley had undergone after the last orogenic movements. Indeed we can say the entire valley, in its partitions of Tsère, Aventine, and Courtod, is the result of the crust l stretching caused by the Mount Rosa lifting up. We carefully look at these and others signs of deep activity: it seems useful for humanity to understand what our Planet is doing, and we can see it on our mountains.

After a quick round trip to the Alpe Varda ruins, we point to the big face on the right (to the west) of the valley, spectacularly cut - halfway up the hillside - by the light strip of the Cime Bianche.
Actually, the white strip is not really related to our ancient ocean. It represents the lagoons that, on the huge beaches of the supercontinent Pangea (250 millions of years ago), preceded the opening of the ocean, with their sands, their evaporation salt, and their coral reefs. Age and contest are the same of the Dolomites; but here later all have been deeply changed during the alpine orogenesis, as a consequence it not possible to find fossils.
The white band separated also the intermediate level of the oceanic crust, on which we are now on, from the upper level outcropping. Above the white band we can find a layer mainly made of chlorite schists, rocks derived by muggy, and calcareous sediments of ocean-basin flloor. The mountains Tournalin and Roisetta, that stand above us, are made of chlorite schists with some inclusions of metabasite, and even less serpentinite.

On the stony slope that goes down from Alpe Ventina, the path suddenly becomes dusty and shiny, while some stones on the sides show dark embossed crystal as a grater. 150 millions of years ago a splash of oceanic mug (clay, limestone) crept in between the basaltic magma flows, then subducted as all the rest of the oceanic plate. The result is a high pressure ferriferous mica that shines on the path, with clear garnets that sometimes peep out on the stones.

Among the fruits of the wood, one of the most required, especially starting from the seventeenth century, was the charcoal, mainly used in metallurgy. It was produces in small clearings, specially equipped pitches in the wood, by means of conical stockpile of wood conveniently arranged in order to transform, by the heat of the fire – without flames – the wood into coal. The process used to take two weeks of cooking, and other two for the set up and cooling, during this time the charcoal burners worked in pairs in order to always take action in case the fire would have started to blaze, and consequently destroy the charcoal kiln. From the middle of seventeenth century to the end of nineteenth century several regulations issued by: the local community, the Conseil des Commis (Council of the High Officials), and the Savoy court tried to rule the production of charcoal in order to safeguard woods considered essential (food, and soil protection), and on the other side to meet the interest of the production (owners of the woods, metallurgical industrials and their customers, among them the Savoy arsenale/weaponry).

Near by the torrent, we are walking on the woody bank which is made up of debris in blocks, generally of small size, fallen from the overlying wall, especially from the higher parts: chlorite schists and white band. This availability of calcareous material together with the timber of the wood must have suggested the installation of a lime kiln, now worthily illustrated by a large panel placed on the path.

The itinerary 8E then returns a trail, it descends down to quote 1800 m next to a huge boulders (metabasite), collapsed in a humid and steep area, nearly a gorge. On our right, between grass, musk, and shrubs, very discreet, we can find a serpentinite outcrop. The serpentinite rocky surface is smooth and humid, and it is parallel to the slope with a large gutter shaper channel. On top the conduit comes out from a vertical cylindrical cavity that is about 40 centimetres wide and at least half a meter deep on the side of the swiping, and over a meter on the side oriented upstream. Little debris lays on the bottom, and the question is engaging: why doesn't a hole in the grass fill up with soil?
These kinds of erosion forms remain mysterious, they require quite high energies (certainly not the pebble that quietly runs on the bottom …), and relatively short construction times.
It is natural to refer its genesis at the glacial environment, assuming wells under pressure in the thickness of the ice mass above. But the models hypothesized so far seem rather unlikely...
Certaines formes d’érosion restent certes pour le moins mystérieuses, elles nécessitent d’une énergie considérable (ce n’est certainement pas le petit caillou qui creuse tranquille sur le fond du trou) et des temps de réalisation relativement brefs. Spontanément, on s’en remettrait à l’environnement glaciaire qui en serait l’origine, en supposant des puits sous pression dans l’épaisseur surplombante de la masse de glace …Toutefois, ces hypothétiques modèles paraissent plutôt improbables à nos yeux.