The subject of research in this study are German borrowings, which constitute the largest (over 46%) share in the Upper Silesian mining sociolect. The German vocabulary on the basis of the Silesian dialect underwent a comprehensive assimilation to the Polish grammatical system, enriching the vocabulary of the studied sociolect. Attention is drawn to the characteristic acquisition to the Silesian phonetic and morphological system. The loans in the field of morphology are accompanied by various word-formation processes – interesting derivatives are derived from borrowings, as well as derivatives motivated by German basics, created using native (often characteristic dialect) formants. Among German loans, there are also inflections on Polish (dialectal) ground – German nouns adapt to native varieties of paradigms. The article also presents characteristic assemblies created on the basis of the Silesian dialect and interesting adaptations of German compositos, which have strongly grown into the dialect of Silesia as translations of German or assimilated as specific hybrids. Borrowings are often accompanied by semantic changes (narrowing, specialization of meanings or their shifting). The analysis of the material in this sketch proves that the Germanisms in the Silesian dialect paradoxically refer to its Polishness, which can be seen in the degree of their adaptation to the Polish (dialectic) pronunciation – the entire grammatical system.