Tiger Iron

Tiger Iron has a hardness of 7 and is often used for inlays from knife hilts to furniture.  It is made up of undulating layers of golden tiger eye, hematite, and red jasper.  There are a couple ideas of how tiger iron was formed.  Could be that the different layers of sediment were laid down and over the years of heat and pressure metamorphosed into this stone.  Another idea suggests that tiger iron is stromatolites (fossilized algae).  Sediment sticks to mats of microbes living on the ocean floor forming a crust.  A new layer of algae forms on top of that layer, etc.  This results in gentle mounding where a cross section shows each successive layer.   Could be it's a combination of both processes.  What I find interesting is that there is so little known or written about many geological formations.  However, on the Internet, there are literally hundreds of sites cataloging each mineral's "ability" to impart to it's owner the qualities of joy, peace, healing, prosperity, etc.  Similar to the differences between astronomy and astrology.