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Usability of obsidian with special refraction as an ornamental stone by bonding with epoxy resin

Rızaoğlu Tamer, Camuzcuoğlu Murat

Systemy Wspomagania w Inżynierii Produkcji

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2022

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Vol. 11, iss. 2

96--103

EN

Ornamental stones have been used quite a lot from past to present, and they are produced both naturally and synthetically in terms of visuality, durability and rarity. Naturally used ornamental stones are divided into two different classes as precious and semi-precious, and obsidian with two different colors belonging to the Nemrut volcanics used in the study is classified as semi-precious stones. Obsidian is a volcanic glass, showing a special fracture (conchoidal) and fracture surfaces give the rock a distinctive shine. In this study, obsidian was classified by breaking in different sizes (8-4.75 mm, 4.75-2 mm and 2-0.6 mm) in order to achieve this brightness. While black obsidian shards were obtained from 4.75-2 mm in size, brown obsidian shards were obtained from 2-0.6 mm shards and chose with the help of tweezers. Obsidian fragments with both colors were bonded with epoxy resin mixed at a ratio of 2:1 (epoxy and hardener) and placed in jewelry apparatus. The known durability properties and gloss of epoxy and the gloss on the broken surfaces of obsidian have been highlighted, and it has been observed that obsidian which has been used with different cutting and polishing techniques until now, can be obtained as a new product by using binder material. It is suitable to be used as an ornamental stone in jewelry making as a result of binding the obsidian fragments with epoxy by making use of the shines that occur on the fractured surfaces of the obsidian. In addition, it has been revealed that new products can be obtained as a result of bonding many natural rocks and minerals by using different binding materials.

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Obsydian i szkło w chirurgii

Nachyła Olga, Gulczyński Jacek

Szkło i Ceramika

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2020

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R. 71, nr 2

22--25

PL

Chirurgia to temat tak rozległy i skomplikowany jak ludzkie ciało. Specjalizacje są coraz węższe, narzędzia coraz bardziej precyzyjne, historia coraz dłuższa. Największy postęp dokonał się w niej w ciągu ostatnich 100–150 lat, co nie zmienia faktu, że o wiele, wiele wcześniej ludzie badali ciała i sięgali po sposoby równie niebezpieczne co ostateczne, żeby pozbyć się bólu lub przynajmniej go zmniejszyć, usunąć zmianę skórną (np. narośl), czy oczyścić ropiejącą ranę. Do tych celów starano się znaleźć możliwie najostrzejsze narzędzie. Zanim doszliśmy do ostrzy stalowych, doskonale sprawdzały się naturalne surowce… przede wszystkim obsydian.

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Chipped and ground stone implements from the Middle Neolithic site of Polgár 31 (north-east Hungary)

Kaczanowska M., Kozłowski J. K., Sümegi P.

Folia Quaternaria

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2016

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nr 84

5--66

EN

The site of Polgár 31 (Ferenci-hát) is situated on the left bank of the Upper Tisza, within the so-called “Polgár Island”. The site consists of single features dated at the Alföld Linear Pottery Culture (ALP) I-III, while the majority of features belong to the youngest phase (ALP IV) attached to the Bükk Culture. Our analysis focuses on both the chipped stone and the ground stone implements. The most important raw material used for the chipped stone industry of ALP IV phase was obsidian, followed by limno-hydroquartzites. Extra local raw materials played a minor role. Both in the case of obsidian as well as limnohydroquartzites on-site production was limited, while most artefacts were produced off-site. The structure of retouched tools shows that end-scrapers dominate slightly over marginally retouched blades. The most commonly exploited raw material in the ground stone industry were various types of rhyolites deriving from the areas 40 to 50 km north of the site. Among tools predominate implements related to food preparation such as a variety of grinding stones, pestles, grinders etc. As part of rituals these tools were destroyed. Sometimes the fragments were used for crushing mineral dyes. Both: fragments of ground stone as well as chipped stone tools occur also in the graves.

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Obsydian w kulturze Majów

Łasisz M., Łasisz M.

Szkło i Ceramika

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2014

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R. 65, nr 6

32--33

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Mineralogia i struktura wybranych surowców jako czynnik ich jakości

Pawlikowski M., Wróbel M.

Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering

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2014

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nr 18

1--8

EN

Paper present results of mineralogical examination of various genetic types of flints and obsidian were performed using polarizing light microscopy, SEM and EDX methods were performed during last 3o years. Various method were used for determining possible relations between internal structures of these raw materials and relations to the best directions for processing. Analyses showed that the best directions for preparation of flint implements are parallel to directions of optical orientation of micro crystalline quartz present in flint. This orientation was the result of the recrystallization process of silica from opal to chalcedony and quartz. The type of processes known as ageing of silica active and observed in flint nodules have persisted for a million years. The growth of microcrystals in primary opal of flints goes a specially well perpendicularly to the direction of stress, i.e., perpendicular to the thickening of rock layers (mostly limestones). Performed investigation confirmed the primary flint nodules formed in situ from sponga organisms show regular nodule shapes. Secondary flints formed due to migration of dissolved silica in deposited sediment had mostly irregular shape. Secondary crystals of quartz present in these flints do not show space orientation and because of this the secondary flints are bad for knapping