Young Blonde Girl With Blue Eyes Takes Off Her Bra Near Sedimentary Rocks At The Sea Coast

• Siliceous sedimentary rocks are almost entirely composed of silica (SiO2), typically as chert, opal, chalcedony or other microcrystalline forms.
• Iron-rich sedimentary rocks are composed of >15% iron; the most common forms are banded iron formations and ironstones
• Phosphatic sedimentary rocks are composed of phosphate minerals and contain more than 6.5% phosphorus; examples include deposits of phosphate nodules, bone beds, and phosphatic mudrocks