Any idea what kind it is?

  • 1984@lemmy.today
    link
    fedilink
    English
    arrow-up
    3
    arrow-down
    1
    ·
    11 days ago

    I asked chat gpt because I was curious…


    The rock appears to be iron-stained sedimentary rock, most likely:

    Sandstone or siltstone

    Reasons:

    Brown/yellow coloration typical of iron oxide (limonite/goethite) staining

    Visible layering and flaking, suggesting sedimentary bedding

    Fine-grained surface (no large visible crystals)

    Breaks along planes rather than showing crystalline fracture

    The reddish area

    The darker red patch may be:

    A small iron-rich concretion

    Or possibly a fragment of jasper (iron-rich microcrystalline quartz) embedded in the host rock

    Less likely options

    Not granite (no visible interlocking crystals)

    Not basalt (wrong color and texture)

    Not metamorphic schist (no clear foliation or mica sheen)

    If found in Scandinavia, this type of iron-stained sandstone/siltstone is common in sedimentary formations and glacial transport deposits.

    For more certainty:

    Check if it scratches glass (quartz-rich sandstone will)

    Drop vinegar on it (if it fizzes, it contains calcite → limestone component)

    Note where it was found (coastal, inland, quarry, etc.)

    Most probable identification: Iron-rich sandstone or siltstone.