The fantastic zeolite occurrence known as “Das Antas”


The story of these zeolites.
In the international market for collectible minerals, at the beginning of the sixties, suddenly appeared marvellous samples from the state of Rio Grande do Sul in southern Brazil: on basaltic rock or without matrix, there were green apophyllites with bow-tie shaped stilbites, radiated white “natrolites”, yellow stellerites, laumontites, heulandites and, rarely, some quartz. Impressive were the green crystals of apophyllite, to up to 20 cm of edge, and the “natrolites”, reaching 25 cm in length. The pieces were sold by weight, and a piece with much rock and few crystals was more expensive than a nice grouping formed only by crystals. A complete description of the occurrence can be found in the german mineralogical magazine LAPIS, Year 3, Number 01, from January 1978, written by the famous collector and mineral photographer Dr. Werner Lieber, from Heidelberg in Germany. These samples could be seen in different places: the famous gemmologist Georg Wild, from Idar-Oberstein, sold some; others have only decorative purposes, as the one in the vitrine of a jewelry shop in the city of Heilbronn; almost all the big international collections have one of these samples in their collection, like the Geological Institute of Heidelberg, in Germany, and the Smithsonian Institute, in Washington D.C., USA.



The sample of the Mineralogical Institute of Heidelberg (1,2 x 0,8 m!) with the label. The sample belongs to Prof. Hermann Bank from Idar-Oberstein, who lent it to the Institute. Pictures and permission for their use from Volker Betz, Germany.


The Problem of the Origin

The occurrence became famous in the international mineralogical literature as “Das Antas”, and it was known that it was related to the construction of a tunnel in the valley of the “Das Antas” river, near the city of Bento Gonçalves in the state of Rio Grande do Sul, as informed by Prof. João Ernesto de Souza Campos to Dr. Werner Lieber (Magazine “Der Aufschluss”, 1965). And now you can see what we discovered related to this ocurrence.

The International Context.

To evaluate correctly the importance of this occurrence we must take a look on the places known for its zeolites at this time. Iceland, of course, than the Färoer Islands, Germany, Hungary, Austria, Australia and others of minor importance. Nothing was known from South America. And from there, suddenly, appeared something never seen before. Green apophyllites and uncolored scolecites which were the biggest and most beautiful collectors had seen until then, as informed by Dr. Lieber. It was a sensation !! Only a decade and a half later the first Indian zeolites appeared at the Mineralogical Congress of Munich, with their origin as badly informed as the Brazilian stuff. “Take it or leave it” was the spirit on this occasion in Munich, informs Dr. Lieber. Today the Indian material dominates the market for collection zeolites. Beautiful, cheap or expensive, they are collected professionally in more than 800 quarries in the region formed by the cities of Mumbay (former Bombay!), Nasik and Poona, in India. A single company from there brought 150.000 pieces to the Tucson Show of 2001. And probably the other shows repeated this performance.

The necessary corrections

To start with the corrections of the story, let’s look at the “natrolites” sold at that time. Very quickly the European collectors realized that the minerals were, in reality, scolecites. But here in the city of Porto Alegre the tale of the “natrolites” was still told unttil few years ago. Wrong. We never found natrolites here in Rio Grande do Sul. Mesolites, yes, OK, according to X Ray Diffractometry, but never natrolites (position of Feb. 2005). From this occurrence, internationally known as “Das Antas”, our Museum stil has some 115 samples, usually small and, this intrigues us a lot, none of them with scolecite. We suppose that the real good pieces were taken abroad, the bad ones stayed here.


This sample belongs to the zeolite specialist Rudy Tschernich, from the Rice Mineral Museum, Hillsboro, Oregon, USA. Mr. Tschernich has a collection of 12.000 pieces and a zeolite with his name, the Tschernichite. The size of this sample is 24 x 17 x 11 cm.


How were the zeolites of “Das Antas” found?

In the fifties the Federal Government decided to build the “Tronco Principal Sul” (TPS), a new branch for the Federal Railways (Rede Ferroviária Federal SA - RFFSA), connecting São Paulo city, in the state of São Paulo, with the city of Rio Grande, located next to the connection of the Patos Lake (a lagoon, of course) with the ocean, in the state of Rio Grande do Sul. The construction of the railway was done by the army, with 3 battalions: the 2nd Batalhão Rodoviário, the 3rd Batalhão Rodoviário and the 1st Batalhão Ferroviário. “Rodoviário”, in Brazil, means something related to highways, “Ferroviário” means something related to railways. It sounds a little bit strange that battalions with this name constructed a railway, but usually these battalions were requested for many different constructions, like airports, harbors, houses and so on.

The 2nd Batalhão Rodoviário was located in the city of Lages, in the state of Santa Catarina, until 1970, when it was transferred to the city of Santarém, in the state of Pará, changing its name to “8th Battalion of Constructing Engineering” (8º Batalhão de Engenharia de Construção). The 3rd Batalhão Rodoviário stayed in the city of Carazinho, in the state of Rio Grande do Sul, until 1970, when it was transferred to the city of Cuiabá, in the state of Mato Grosso do Sul, with the name of “9th Battalion of Constructing Engineering” ( Batalhão de Engenharia de Construção).

We asked people of this Battalion if they had any information on the minerals and received the following e-mail:
Sent: Thursday, February 21, 2002 8:51 PM
Dear Prof. Heinrich,
As you asked for, we verified in the archives of the Battalion (now located in the city of Cuiabá - state of Mato Grosso) and couldn’t find any register, file or picture of the mineralogical material found during the construction of that railway. If you have any question, please contact us.
Best regards,
1st Ten. Lima

The 1º Batalhão Ferroviário (1st Railway Battalion) was stationed in the city of Bento Gonçalves, with outposts in the cities of Roca Sales, Violanda, Santa Tereza and Jaboticaba, summing up 1500 men. Visit the homepage of the battalion ! This battalion was responsible for the construction of the part of TPS between the cities of Roca Sales and Vacaria. We localized a man of this battalion, Lieutenant Toassi (see his report below).

The building of the railway started in 1958 simultaneously in different places, and so always 5 or 6 tunnels were being built at the same time. The TPS was finished in 1966, being inaugurated without any ceremony by the president of Brazil, General Emílio Garrastazu Médici. Not even a newspaper appeared to shoot a picture. It was the darkest time of the military dictatorship which ruled Brazil during 20 years, until 1984.

The trace of TPS

The part of TPS of our interest starts in the city of Lages in the state of Santa Catarina and runs through the cities of Vacaria, Caxias do Sul and Lajeado in the state of Rio Grande do Sul. The corresponding maps of the Brazilian Army, scale 1:50.000, are the following: The TPS starts in Lages, Sheet MI 2922/1. This part has no tunnels. But on the next sheet, Vigia, MI 2921/2, there are 3 tunnels, one of them 1200 m long. The railway continues to the sheet of Capão Alto. Sheet Capão Alto, MI 2921/4: there the railway shows 13 tunnels, one of them with 1500 meters and another one with 1000 meters, besides smaller ones of 100 and 250 meters. The next sheets are those of Vacaria-Norte, MI 2921/3 e Vacaria, MI 2937/1, without tunnels. The following sheet, Guacho, MI 2936/2, shows a tunnel of 500 meters. Continuing in the general direction southwest, the railway enters the sheet São Paulo, MI 2936/1, with 9 tunnels, among them one with 1000 meters and another one with 300 meters. On the sheet of Antônio Prado, the historical city of Italian colonization, MI 2936/3, there are 4 tunnels, with 250, 500, 750 and 1000 meters in length. Next sheet is Bento Gonçalves, MI 2952/2, with 7 tunnels, 4 of them are big with some 1000 to 2000 meters in length. Now the railway enters the sheet called Encantado, MI 2952/1 with a small tunnel of 200 meters and a really big one of 3000 meters. On the last sheet of our interest, Lajeado, MI 2952/3, a last tunnel with 200 meters can be found. From now on the railway leaves the basaltic rocks and enters the sedimentary gondwanic rocks in the south of the state of Rio Grande do Sul.

As you see, there are, summing up, 40 tunnels with a total length of more than 25 kilometers, always big enough for a completely loaded train ! Imagine the volume of basaltic rocks which came out of these tunnels ! What a formidable opportunity for zeolite hunting ! What an achievement was the construction of this railway from 1958 to 1966. The homepage of the battalion shows another memorable construction: the second-highest railway of the world, 143 meters high.

The report of the Lieutenant

For the reconstruction of the history of these zeolites we found one of the men who helped in the building of the railway: Lieutenant R/1 Olísio Toassi, from the 1st Railway Battalion, now living in the city of Lages (Dr. Carílio St, 85, Bairro São Cristóvão, phone +55 49 223-2265).

Telling us his story of the railway, the Lieutenant said that he never saw crystals like these zeolites during the work on the part of the railway conducted by his Battalion. He first saw the “Das Antas” zeolites on our homepage. In the many cuts made, the kilometers and kilometers of tunnels and in the great number of quarries opened during the railway construction for crushed stone, nothing exceptional appeared. He remembered that near the Santa Tereza tunnel, both north and south of it, crystals appeared, but small ones.

We inspected this tunnel with the Lieutenant in February 7th, 2002. Santa Tereza is a small bucolic town with 500 inhabitants next to the Taquari river, 25 km west of the city of Bento Gonçalves in the state of Rio Grande do Sul. The warehouse is 100 years old, the port was very busy until it filled up with sand decades ago and the paved road to the town, 27 km long, is now called the “Vine Valley”, with thousands of vineyards between the typical araucaria trees of the region. Next to the road there are many canteens who offer vine degustation for free. It’s a fantastic trip if you don’t know it (and also for those who already know it, of course!).

The tunnel is number 19, 1850 meters in length, built by the 1st Railway Battalion from 1958 to 1961. The walls are not covered and you can’t see any holes of geodes, even small ones, in the black rock forming those walls. The same happens on the cuts near the tunnel. Other people interviewd said the same: no crystals. A cut 500 meters south of this tunnel showed crystals (below a small bridge) which were collected by the soldiers. But the lieutenant doesn’t remember any other person besides the battalion people collecting any material. We showed him a scolecite aggregate of very poor quality and not even this he said was found during the construction.

In 1971 the battalion was transferred to the city of Lages, in the state of Santa Catarina, to build the railway between the cities of Muçum and Passo Fundo, the Wheat Railway, where they found amethysts in cuts. From this occurrence we know nothing.

The collection of the zeolites

These apophyllites and zeolites were collected by Geology professors and students and by a mineral dealer.

This material was collected three times by students of the Geology Course of the School of Geology. In 1956, the federal government started the “Campaign for Formation of Geologists - CAGE” , with 4 Geology courses in Brazil, one of these in Porto Alegre. In 1957, the first group of 25 students started the new program and from than on regular field trips were made to geologically interesting places in Rio Grande do Sul and other places. At least once the collecting was professional, made with a truck, as cited by Prof. Clóvis Carlos Carrarro.



A typical “Das Antas” piece, as the ones we have here in the Museum. The sample and the picture are from Volker Betz, Germany.


Report of the first field trip.

The first field trip happened in July 1960 with the 2nd Geologists Group (in reality Geology students) from the School of Geology, who graduated in 1961. They visited the famous White Column, a road which goes up to the basaltic rocks, cutting through all the sedimentary gondwanic rocks from the Paraná Basin. The name was given by I.C. White in 1908. The road is impressing, winding up through the valley in hundreds of curves until it reaches the top of the basaltic lava flows.

The trip went from Porto Alegre to Torres, in the state of Rio Grande do Sul, through Arambaré, Tubarão, Lauro Müller, Rio do Sul and Lages in the state of Santa Catarina and then returning to Vacaria, Caxias do Sul and Porto Alegre, again in Rio Grande do Sul.

Participating were Heinz Peter Lindstaedt, Carlos Bortoluzzi, Zuleika Lopes Carreta and others, with the american professors who teached in the School of Geology: Max Troyer and Robert Morris. The trip used two Apache jeeps, brought by the American through the cooperation program called "Point IV", and a Rural Willys car. The “Point IV” was a program started in 1960 with the US Department of State and the US Geological Survey.

Between the city of Lages and the border with the state of Rio Grande do Sul, formed by the river Pelotas at the place(?) called Passo do Socorro, more or less half the way up between the level of the Pelotas River and the level of the city of Lages, on the road known as BR-116 (formerly BR-2), there was a camp of the Road Battalion east of the road, 20 or 30 km from Lages. The Battalion was building the tunnels of the Tronco Principal Sul railway branch of RFFSA, the federal railway company. Near the camp they had a quarry for crushed stone used by the construction of the road BR-116, also being built at that time. The name of the quarry is “Bela Vista” and there is an abandoned white house in front of it. Next to it there is a high tension electric line.



This sample of “Das Antas” is in the American Museum of Natural History, in New York. Picture from Geol. Pércio de Morais Branco (on the picture), from CPRM - Serviço Geológico do Brasil, responsible for the MUSEU DE GEOLOGIA (www.cprm.gov.br/sureg-pa/museu.html).

The geology students went to the quarry to collect some zeolites and apophyllites. A small quantity had been set aside by the workers, but few pieces could be collected. Later the soldiers showed them 5 or 10 dynamite boxes with good samples piled up in them. These samples were collected by the workers from this quarry as well as from other places. Each student picked up some samples and the professors got some for the mineralogical collection of the School of Geology, today the “Museum Luiz Englert”.

This was the first visit. They brought back apophyllites and scolecites and some other pieces from a quarry and from other unknown places, but not from a tunnel.

Prof. Nilo told us that in his office, shared with Profs. Roberto Hamilton Morris and Aziz Nacib Ab Saber, where he worked since the end of 1960, there was a board with a good quantity of samples with green apophyllites and others. But he doesn’t know if these samples came from a tunnel or from other places.


Report of the second field trip

In 1962, another group of Geology students travelled to Lages with the professors Mackenzie Gordon Junior, Max Troyer and Juan Goñi and collected, from a tunnel(?), many samples with apophyllites, scolecites and others. The corridor of the bus used on that occcasion was filled with samples and an accompanying Apache jeep was also filled. Prof. Goñi sold all these samples to the BRGM (Bureau de Recherches Geologiques et Mineralogiques) in France, of which he later became director.
This report confirms an information of Dr. Werner Lieber, who cites, in the magazin “Der Aufschluss”, from 1965 (Year 16, Book 2, page 29): “A very similar ocurrence was found 5 km south of the city of Lages, in the state of Santa Catharina”. Dr. Lieber became, due to this story, a very active friend of our Museum, making contacts in Germany for us. He informed us that in his book “Der Mineraliensammler”, in its first edition, in 1963, the ocurrence “Das Antas” was already listed, with the information “Cruzeiro do Sul”. In its 7th edition, from 1978, it cites that “similar ocurrences were found more to the north, near Lages - SC”. Note the plural of “ocurrences”!
The town of Cruzeiro do Sul is located near the city of Estrela, in the state of Rio Grande do Sul, a region without basalt. So we have to consider one more place with this name.


Report of the third field trip

During the second semester of 1962, one more field trip was made to the region of Lages. The group included the professors Juan Goñi, Hector Goso, Aziz Nacib Ab Saber and Patrick Delaney, with the students Raul Mosmann, Giovanni Toniatti and Jair Ferreira Pinto. In a roadcut made for a railway or highway, big geodes with very pretty crystals were seen. This roadcut is in the city of Lages. They used two Apache jeeps for this field trip.


The report of Eugênio Giovanella

From May 1st to 5th, 2002, we participated in the 2nd International Gem and Mineral Show of Soledade, in the city of the same name, showing zeolites. As we were still organizing the samples in the vitrine, we were interrupted by a sympathetic old man who asked us, pointing to the big “Das Antas” piece in the exhibit: “Are these calcites from Veranópolis or from Lages?” Except for the “calcites”, the question was exactly right. So we asked him to take a seat and started to write the story of Mr Giovanella.



Eugênio Giovanella during the Gem Show de Soledade - 2002

69 years old (in 2002), Eugênio Giovanella started early with his collections. At the age of 16, living in Lajeado, in Vila Progresso, he was working in the amethyst and topaz (citrine) mines.
Dr. Haroldo Burle Marx, brother of the famous Roberto Burle Marx, came to Rio Grande do Sul to see the mining of the stones in the state. On this occasion he invited Eugênio to work with him with stamp collections.
Later Eugênio travelled to Rio de Janeiro in the business of stamp collections. But, as he already knew stones, he built a collection of stones. After 22 years searching for rare stones his collection now has 1200 pieces.
When thematic shows started to be organized (wine, grapes, etc,), as in the city of Caxias do Sul, Eugênio participated and, in 1966, was the first person showing minerals in a show, this year in the city of Bento Gonçalves, during the first Fenavinho, a wine festival. Other shows followed, as in Caxias do Sul in 1967, in Governador Valadares and in Bruxelles.

While travelling from Bento Gonçalves to Veranópolis, more or less in 1958, he visited the tunnels and found the pretty green “calcites”. So he tried to sell these minerals, which became famous as “Das Antas”.

He found the workers of the Selvino Dal Bó company, hired for the building of part of the TPS railway with at least 3 tunnels and many cuts. The minerals were found in the tunnels and in the many cuts made for the railway in the hills.

There he learned that the rocks with the minerals were first thrown in the Antas river who passes besides the railway. Then some workers set some material aside due to its beauty. So Eugênio told the men he would buy the minerals if they set them aside. In this way the businessman travelled once a month to the construction site with his jeep, during two years. Many minerals were bought this way.

But then the ocurrence of these minerals in the tunnels exhausted. From 1962 or 1963 on the same kind of mineral was found in the city of Lages, in a cut next to the railway, a few kilometers south of the city. There the workers collected the minerals which were again bought by Eugênio. The volume of material was much smaller than that found in the tunnels, and then the work on that roadcut stopped and no more minerals were available.

The next step was to sell the stones, never seen before until then. Working almost in consignation, Eugênio sold some pieces to find buyers abroad.

One of the companies who bought pieces was Chupp, owned by three brothers who left Germany during World War II, and established a shop on the Praça das Flores (Flower Plaza) in Rio de Janeiro. They had never before seen anything likely. Some pieces were sold to H. Stern through its buyer, nicknamed “Lilico”. Another buyer was Hugo Zimmer, from Rio de Janeiro, who had a relative in Idar-Oberstein, in Germany. Today a son of Hugo, Carlos Hugo Zimmer, is a gem stone buyer in Teófilo Otoni, specialized in Aquamarine.

Finally, another buyer was Jaques, from the Amsterdam company, owned by the french Julio Sauer, who was also surprised by this new material.

Exportation, in those years, could only be made in Rio de Janeiro, through the “Rendas Internas” department, and it took 8 to 10 days after the stones arrived in Rio de Janeiro. A day had to be scheduled for the inspection of the boxes, to check if they met with the document called “Manifesto”. The exporting was made in wooden boxes.

Today a sample of the minerals can be seen in the cave Our Lady of Lurdes, just next to the school, in the city of Veranópolis. There the minerals were glued with cement to the walls of the cave, being crystals of that region.


Our Acknowledgments

Many people helped us here: Volker Betz and Dr. Werner Lieber, from Germany, professors and servants from Geosciences Institute of UFRGS University: Profª Zuleika Carreta Corrêa da Silva, Prof. Nilo Clemente Eick, Profª Tania Brum, Prof. Flávio Koff Coulon, Prof. Clóvis Carlos Carrarro, Jair Ferreira Pinto, Prof. Heinz Peter Lindstaedt, Prof. Luiz Roberto Martins e Prof. Franz Semmelmann, Ivone Cernichiaro (the driver "Capelão") and others. We have to thank all of them for their collaboration in the reconstruction of this fascinating story.