The amber-bearing deposits of northern Poland are genetically linked to the riverine deposits of the Paleogene Gda\u0144sk delta, accumulated approximately 30\u201340 million years ago along the northern shore of the Upper Eocene sea. The amber-bearing formations were transported to the sea by the hypothetical Eridan river (Kosmowska-Ceranowicz, 1989), and subsequently covered by thick layers of Paleogene, Neogene, and Quaternary sediments accumulating in subsequent geological periods. Currently, the Upper Eocene amber-bearing deposits are generally found at depths ranging from 50 m (in Sambia) to 150 m (in the Ch\u0142apowo region) below ground level.<\/p>\n\n\n\n
On the S\u0142upsk Plain, amber was found as a result of glacial transport during the Pleistocene. Amber lumps were carried along with the sediments in which amber had previously accumulated, in formations known as \u201eblue earth.\u201d These formations are actually grey-green in colour and consist of sandy silts and silty sands with glauconite and muscovite. They are associated with the Polczynian link of the lower Mosina formation (Kramarska et al., 2008). The name \u201eblue earth\u201d itself was likely given by German miners who, working in the lamplight of underground amber mines on the Sambian Peninsula, referred to the sediment in which amber was most often found in this way. In artificial light, the greenish glauconite, one of the minerals in this sediment, took on a bluish hue.<\/p>\n\n\n\n
\u201eBlue earth\u201d packets were torn away from Paleogene strata in the region of present-day Gda\u0144sk Bay and transported by the ice sheet during the last glaciation. Such torn-off fragments, like glacial erratics known from amber-bearing deposits, are found precisely on the moraine elevations around Mo\u017cd\u017canowo. However, it should be noted that in the S\u0142upsk region, the ice sheet left behind many amber-bearing Paleogene glacial erratic deposits. This is evidenced by both historical records concerning the search for raw materials, usually conducted by S\u0142upsk amber prospectors, as well as accidental finds during well digging or construction work. Numerous glacial erratics in the S\u0142upsk region are also documented by contemporary geological research conducted as part of the geological mapping for the Detailed Geological Map of Poland at a scale of 1:50,000.<\/p>\n\n\n\n
In Mo\u017cd\u017canowo, amber found in Pleistocene deposits was already exploited in the 17th century. Many tons of raw material were probably extracted here during the period of prosperity (1784\u20131786). In order to exploit the deposit, the then owner of the mine, the Jew Liepmann, sometimes employed up to 100 amber miners, who dug numerous open-cast mines approximately 4 m in diameter and reaching a maximum depth of 6\u20137 m (Ma\u0142ka 2010). The article by B\u0142aszak (1987) stated that the depth of the mines in Mo\u017cd\u017canowo could have been over 20 m at that time, which results from a mistranslation of archival German-language materials cited by the author. This error has been repeatedly reproduced in numerous scientific and popular science publications.<\/p>\n\n\n\n
After cutting the groundwater level, the mine was flooded and Liepmann withdrew from his mining activities. According to some sources, the reason was also the deep religiosity of the Jew, who did not allow employees to extract amber on the Sabbath. After this period, amber mining in the Mo\u017cd\u017canowo region was most likely continued by other owners.<\/p>\n\n\n\n
Previously unknown archival sources concerning the historical exploitation in Mo\u017cd\u017canowo (and former amber mines in Poland) are topographical maps on a scale of 1:25,000, known as Urmesstischbl\u00e4tter, held by the Staatsbibliothek zu Berlin \u2013 Preu\u00dfischer Kulturbesitz. The Urmesstischbl\u00e4tter maps were developed in the 19th century by the Prussian General Staff. They were created with the aim of comprehensively mapping the territory of Prussia with a uniform, accurate, and detailed topographical map. Due to the highly valued properties of succinite, the locations of open-cast amber mines were also marked on them (Ma\u0142ka, 2016). These maps are unique, existing only in manuscript form and never having been published. The map sheets on which the amber deposits are located currently represent the oldest reliable depiction of post-mining areas based on geodesic measurements (triangulation). In the case of Mo\u017cd\u017canowo, a valuable source material is a sheet from an old Urmesstischbl\u00e4tter map with the handwritten insignia \u2013 319, Peest (reference number N 729\/319). The map was developed in 1836 by a Prussian lieutenant with a Polish-sounding surname, Glisczinski. Based on this map, we can infer that in Mo\u017cd\u017canowo, amber was mined in the early 19th century in four active open-cast mines (surface pits), possibly with shallow shafts. The mines visible on the surface were circular or elliptical in shape, several metres in diameter, with clearly marked spoil heaps around the openings (Fig. 1).<\/p>\n\n\n\n
Interest in the Mo\u017cd\u017can\u00f3wek amber deposit was renewed in the second half of the 20th century. Numerous cartographic works were carried out at that time during the development of the Detailed Geological Map of Poland on a scale of 1:50,000 (Uniejewska, Nosek, 1982), as well as deposit studies, which aimed, among other things, to measure the basic parameters of the deposit, estimate amber resources, and determine the stratigraphic position of the formations accompanying the mineral deposit (B\u0142aszak, 1978). In the area of Mo\u017cd\u017can\u00f3wek and the localities of Zaleskie, Zab\u0142ocie, and W\u0142ynk\u00f3wko, several Palaeogene glacial directions were documented in the till horizon of the Pomeranian, Pozna\u0144, and Leszno phases (Uniejewska, Nosek, 1982). However, amber did not occur in all tills, and the size of the amber nugget fractions, as well as the quantity and quality of amber in individual amber-bearing horizons, was very uneven.<\/p>\n\n\n\n
Research has shown that succinite in Mo\u017cd\u017canowo is found at several levels: shallowly beneath the surface in Quaternary sediments (in glacial erratics) and deep below 100m in Palaeogene sediments, i.e. in the \u201eblue earth\u201d which is an extension of the Sambia-Ch\u0142apowo deposit. The succinite deposit in Mo\u017cd\u017canowo was identified based on 15 boreholes (Fig. 2), with four boreholes (M-I, M-II, M-5, M-6) reaching the bottom of the sediments forming the Palaeogene erratic. Boreholes M-I and M-II penetrated the entire Quaternary complex and reached the in situ Palaeogene sediments (B\u0142aszak, 1987). The glacial erratic sediments are represented by grey-green sandy silts and silty sands with glauconite, muscovite and succinite, laminated with sand and clay, locally slightly carbonised, with fragmented plant remains, xylite and charred detritus. Core analysis also revealed the presence of poorly sorted, variously sized quartz sands with gravel, brown coal, as well as iron and manganese aggregates within the erratic profile. The glacial erratic sediments are heavily disturbed glacitectonically and slickensided, with visible slip planes (B\u0142aszak, 1987).<\/p>\n\n\n\n
The documented Paleogene glacial till lies at a shallow depth of 2.5 \u2013 6.0 m (according to Uniejewska, from 1.7 m) below ground level. The thickness of the \u201eblue earth\u201d found in the karsts in Mo\u017cd\u017canowo reaches values between 12.4 \u2013 33.8 m. The base of the Paleogene glacial till is located at a depth of 18.4 \u2013 37.3 m below ground level (average 27.3 m b.g.l.). B\u0142aszak (1987) dated the sediments as Lower Oligocene, although they are most likely Upper Eocene or Eocene-Oligocene boundary deposits. The upper part of the investigated till consists of younger, Miocene deposits, which are developed in the form of black and dark brown carbonaceous silts. The geological structure of the amber deposit and the location of the performed boreholes are shown in the geological cross-sections: longitudinal and transverse (Fig. 3) and the map (Fig. 2). The size of the amber found in Mo\u017cd\u017canowo ranges from 2 mm to 7 cm. Generally, fine grains predominate, however, a large weight proportion of coarse fractions above 20 mm positively indicates the quality of the deposit. Transparent, sharp-edged amber dominates, often surrounded by weathering crust. The surface of the lumps is covered with numerous grooves, sometimes filled with clayey matter (Fig. 4). The geological studies carried out have allowed for the estimation of raw material resources, still awaiting exploitation, at nearly 20 tonnes (B\u0142aszak, 1987). Unfortunately, a significant proportion of clayey material in the deposit and the lack of access to a water source, which would enable hydraulic mining, present a certain difficulty for potential exploitation. Currently, in the vicinity of Mo\u017cd\u017canowo, outside the area investigated last century, intensive prospecting for amber deposits is being carried out (information from the provincial geologist M. Kowalski). Time will tell whether these efforts will be successful.<\/p>\n\n\n\n
Mo\u017cd\u017canowo is not only a potential area for mining investment but also a unique geotourism attraction. Within the area of the former amber mine in Mo\u017cd\u017canowo, a geological monument of inanimate nature was designated by virtue of the Pomeranian Voivode\u2019s Decree of 07.11.2001. However, the location of the geological site presented in the Geo-service Maps of the General Directorate for Environmental Protection (GDO\u015a) does not correspond to reality. The preserved mine workings are located within wooded areas on agricultural land, whereas on the GDO\u015a map, a picturesque avenue planted in a circle, on the property of amber prospector N. Kalski, is identified as the former amber mine. In aerial photographs, this place, due to its spherical shape, resembles an amber mining excavation (fig. 2).<\/p>\n\n\n\n
The Mo\u017cd\u017canowo geo-site is listed in the \u201eCatalogue of geotouristic objects in Poland\u201d (S\u0142omka et al., 2006), for this reason it is quite well-known and frequently visited by, among others, university lecturers, students, and geology enthusiasts. Traces of contemporary, both legal and \u201ewild\u201d (uncontrolled) exploitation from the 20th century are superimposed on the former amber mining. Evidence of old exploitation is visible within the infield tree stands; these are small, irregular, funnel-shaped pits a few metres in diameter. <\/p>\n\n\n\n
The preservation of Mo\u017cd\u017can\u00f3w's geological and cultural heritage should be a priority for local authorities. This location also offers unique and innovative investment opportunities in geotourism.<\/p>\n\n\n\n
B\u0142aszak M., 1987, Amber in Tertiary deposits in the vicinity of Mo\u017cd\u017canowo near S\u0142upsk. Biul. Pa\u0144stw. Inst. Geol. 356: 103-119, Warsaw. Mo\u017cd\u017canowo is not only a potential area for mining investments but also a unique geotouristic attraction.<\/p>","protected":false},"featured_media":26929,"parent":0,"menu_order":0,"template":"","meta":{"_acf_changed":false,"slim_seo":{"title":"Mo\u017cd\u017canowo w rejonie S\u0142upska \u2013 geologia plejstoce\u0144skiego z\u0142o\u017ca bursztynu i historia jego eksploatacji - Amber Portal","description":"Mo\u017cd\u017canowo is not only a potential area for mining investments but also a unique geotouristic attraction."}},"tags":[],"lokalizacja":[],"temat":[223],"class_list":["post-17376","bursztyn","type-bursztyn","status-publish","has-post-thumbnail","hentry","temat-bursztyn-baltycki"],"acf":[],"_links":{"self":[{"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/bursztyn\/17376","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/bursztyn"}],"about":[{"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/types\/bursztyn"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/media\/26929"}],"wp:attachment":[{"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/media?parent=17376"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/tags?post=17376"},{"taxonomy":"lokalizacja","embeddable":true,"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/lokalizacja?post=17376"},{"taxonomy":"temat","embeddable":true,"href":"https:\/\/amber.com.pl\/en\/wp-json\/wp\/v2\/temat?post=17376"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Literature:<\/strong><\/p>\n\n\n\n
Kosmowska-Ceranowicz B., 1989, The Mysteries of Amber. Warsaw. Sport i Turystyka.
Kosmowska-Ceranowicz B. (ed.), 2002, Finds and Former Amber Mines in Poland, 158, Stach Konwa Regional Library, \u0141om\u017ca.
Kramarska R., Kasi\u0144ski J., R., Sivkov V., 2008, Palaeogene amber *in situ* in Poland and neighbouring countries \u2013 geology, exploitation, prospects. *G\u00f3rnictwo Odkrywkowe* 50, 2\u20133: 97\u2013110. Wroc\u0142aw.
Ma\u0142ka A., 2010, Former mines and exploitation methods of Baltic amber deposits. Bulletin of the Polish Geological Institute, 439: 491\u2013506, Warsaw.
Ma\u0142ka A., 2015, In the Footsteps of Amber Mining in the Pomeranian Voivodeship. Acta Universitatis Lodziensis. Folia Geographica Socio-Oeconomica 22 \u2013 Historical Geography & HGIS. \u0141\u00f3d\u017a: 65\u201386.
S\u0142omka T., Kici\u0144ska-\u015awiderska A., Doktor M., Joniec A., 2006, Catalogue of geotouristic objects in Poland, 170\u2013171, Krak\u00f3w.
Uniejewska M., Nosek M., 1982, Detailed geological map of Poland on a scale of 1:50,000, sheet Ustka (9), Wydawnictwa Geologiczne.<\/p>","protected":false},"excerpt":{"rendered":"