The mining facility with a resonant name ‘Aurelia’ was carved into the steep western slope of the Kaczawa Valley in Złotoryja, below the church and cemetery on St. Nicholas Mountain. Despite the well-known saying that ‘the deceased from Złotoryja lie in gold,’ the adit was carved by hand in search of not gold but copper ore. The mystery of the adit beneath Mount St. Nicholas is evidenced by unconfirmed information that it may be connected to the underground passages of St. Nicholas’ Church.
The workings of the adit beneath Mount St. Nicholas were carved in massive, weakly transformed rocks of subvolcanic origin – the so-called diabases, which occur here in the form of lenses and flat magmatic bodies within the surrounding transformed sedimentary (metasedimentary) rocks – sericitic schists and phyllites of the Kaczawa metamorphic complex. Diabases formed at the bottom of the marine basin that existed in the area of today’s Kaczawskie Mountains and Foothills during geological periods known as the Ordovician and Silurian (485-419 million years ago). The mineral composition of these rocks is dominated by minerals such as albite, epidote, chlorite, calcite, actinolite, and iron oxides. In diabases, calcite and quartz veins are often encountered, which were the subject of interest for miners. These veins formed as a result of the cooling of hot solutions circulating in rock fissures. The solutions contained dissolved metal ions, such as copper and silver, which were encountered during mining operations. Gold, on the other hand, has been found in the sands and gravels overlying the diabases occurring on the southern slopes of the hill. It comes from the same veins that were exploited in the ‘Aurelia’ adit, however, it is so-called secondary gold. It was deposited in river gravels and sands through the erosion and weathering of the rocks where it originally occurred. Therefore, today we can find gold in streams and rivers flowing through the Kaczawskie Mountains and Foothills. In the 17th century, 10.6 grams of pure gold were washed out from 54 tons of sand from Mount St. Nicholas.
The digging of the first adit on the slopes of Mount St. Nicholas (next to the Aurelia adit, there are also two other smaller structures) began in 1661, resulting in the extraction of small amounts of silver and copper. During these works, older adits, probably dating back to the 14th-15th centuries, were discovered. Vertical shafts were dug from the horizontally running adit, reaching the surface. The Aurelia adit in Złotoryja, as one of the few such objects in the Kaczawskie Foothills, has been open to visitors since 1973.
