| Id | Identification Type | Name | Description | Distinguishing Features | Tags |
|---|---|---|---|---|---|
| 13 | Mineral | Palagonite | Yellow or yellowish brown, amorphous to weakly birefringent, heterogeneous material forming through low-temperature hydration and elemental alteration of basaltic volcanic glass. Further alteration of palagonite produces zeolite minerals and smectite clays.
Palagonitized grains may retain glass shard forms. Association with unaltered volcanic glass and other volcanigenic sediment components such as pyroxenes and plagioclase feldspar. |
||
| 164 | Lithofacies | Peat | Lithofacies referring to a sediment consisting of >80% authigenically produced organic matter.
High proportion of organic matter to mineral grains. Organic material may be coarsely fragmentary, or degraded. |
organic-matter fibrous fragmentary bryophyte woody |
|
| 52 | Mineral | Phillipsite | Prismatic, very often as cruciform (cross-shaped) twins or rosettes, colorless with low-moderate relief and low-order birefringence. Phillipsite is a zeolite-family mineral typically formed through alteration of mafic volcanic rocks or tephras, and may be found in association with other zeolites, especially in saline lake or marine sediments. | zeolite | |
| 111 | Mineral | Pirssonite | Colorless, prismatic or tabular, with high-order birefringence and moderate relief. Pirssonite is a hydrous Mg-Ca carbonate mineral found in evaporative environments in association with other saline indicators. | ||
| 54 | Mineral | Plagioclase | Plagioclase is a term for feldspars in the Na-Ca solid solution series. Without twinning patterns, there is no way to tell a difference between Na-Ca feldspars and K-feldspars (microcline and orthoclase). | lamellar-twinning
low-birefringence |
silicate |
| 149 | Contaminant | Polycarb Large Fragment | contaminant | ||
| 150 | Contaminant | Polycarb Small Fragment | contaminant | ||
| 5 | Mineral | Pyrite | Opaque (black). Yellow in reflected light. Pleochroism and birefringence not applicable. Euhedral, framboidal, space-filling shapes. May coat or replace organic matter. Occurs in organic-rich or reduced sediments. Common in lacustrine, wetland, estuarine, and marine environments. | Opaque
euhedral |
Cubic Octahedral Framboidal sulfide |
| 138 | Mineral | Pyroxene | A class of aluminosilicate minerals, many of them iron and/or magnesium-bearing, having wide distribution in igneous and metamorphic rocks and occurring commonly as minor but often prominent constituents in sedimentary environments. In smear slides, Mg-Fe pyroxenes are typically shades of green or brown (depending on mineral species) in plane-polarized light, often display moderate to strong pleochroism, and show moderate birefringence in cross-polarized light. Extinction can be either parallel (minerals in the orthopyroxene class) or inclined (clinopyroxene minerals). Pyroxene minerals have relatively high specific gravity, and will tend to concentrate with other heavy mineral species in winnowed or density-sorted depositional environments. | silicate |
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