The abandoned quarry Hvězda with the length of its wall about 170 m and a height of up to 25 m, located on Mt. Staropacká about 2 km from the town Stará Paka, is known as deposit of many precious stones. The deposits of pyroclastic rocks of phreatomagmatic eruption of maar volcano are exposed in this place. Massive amygdaloidal andesitoids and several types of irregular red-brown lenticular positions of tuffites and its agglomerates are present there. Almonds are somewhere plentiful, rare elsewhere, their size range from the cavities with millimeter dimensions to 15 cm in diameter. Moss chalcedony, agate, geodes, and calcite are to be found there usually.
The highest peak of Bohemian Paradise is a part of Ještěd-Kozákov ridge. It was created by uplifting along the Lusatian Fault 5 million years ago and it consists of Paleozoic phyllites, rocks of Carboniferous and Permian Ages, Cretaceous sandstones, and Tertiary basalt. A body of amygdaloidal melaphyres in the Votrubec´s quarry gives the evidence of volcanic activity in the Late Paleozoic Era. Various types of quartz, agate, jasper, chalcedony, zeolites, and more crystallized in the cavities of the melaphyre. Stones from Kozákov were used already by prehistoric hunters. A tourist lodge with restaurant is on the top of the hill, with a new 40 m high publicly available lookout tower offering wonderful view of the Bohemian paradise landscape.
Magmatic gushes at the northern slope of Kozakov
The youngest volcanic activity took place here in the Tertiary period. Basaltic rocks cover the northern slope of the hill. Tephres, which appear at the beginning and in the middle of the volcanic activity, represent only about 5% of the mass produced. Columnar structure is a typical characteristic of igneous rocks that cooled near the surface. The columns of basaltic rocks lined up like organ pipes or presented in fan-like shapes are located on the northern slope. Volcanic bombs can be found on the top of Kozákov as well as in the former volcano crater at Prackov. Green olivine stones are mostly present in the basaltic rocks.
Basalt hill, of similar origin as Trosky, stands in the middle of a sandstone plateau lying in the southwestern part of the Bohemian Paradise about 2.5 km northeast from the town of Mnichovo Hradiště. The highest peak of
Hill Strážník is quite famous and perhaps the only site in Europe, where the Star Quartz can be found. The origin of local unique radial star-shaped quartz is linked to the hydrothermal vein pervading through the melaphyre in the southeastern part of the top platform, called "Boroví". Weathering processes such as erosion, frost and slope sliding in the past caused the distribution of star quartz down the slopes. The maximum reported diameter of radial aggregates was 10cm. Nowadays, the site where the star quartz was found was covered with soil - to prevent further collecting - it was declared natural preserve in 1963.
Hill Zebín is one of the landmarks near the town of Jičín. A marshy landscape with shallow lakes was here about 17 million years ago. Then a hot magma penetrated into it, which was fractured into small fragments due to the reaction caused by its contact with water. However, the strength of the eruption has not increased much. That´s how the tuff cone was created, which was later filled with magma through the dike vein and a lake of lava formed in it. Abandoned quarry lying on the hillside reveals the structure of a scoria cone volcano remnants. A Chapel of St. Mary Magdalene was built in 17th century on the top of the hill.
Zlamaniny by Nova Paka
Sedimentary rocks of Kumburk formation – Štikov arcoses 300 millions years old are shown on the wall of the abandoned quarry. Arcoses are distinctly horizontal and cross-bedded with fluvial channels. There are three silicified wood of Dadoxylon type embedded in various directions and levels inside north wall of the quarry. The biggest of them is about 75 centimetres thick in diameter. Sub vertical dike of Miocene basalt rock with maximal thickness of 1 metre intrudes on the east wall of the quarry. Small basalt bed of breccia structure with typical hexagonal seclusiveness occurs near the bottom of the quarry, it is probably the remnant of volcanic dike channel.