OSI Model - The Lower Layers The bottom four layers of the OSI model are often referred to as the lower layers: â¢ Layer-4 â Transport layer â¢ Layer-3 â Network layer â¢ Layer-2 â Data-Link layer â¢ Layer-1 â Physical layer Protocols that operate at these layers control the end-to-end transport of data
Ross-Simons' Agate Jewelry. Agate is a variety of chalcedony that comes in variety colors making it ideal for all kinds of jewelry designing. Blue agate is as expected, light blue. Moss agate is dark green, often with clear patches.Tree agate is green and white.gate: Stripes Earned by Nature. With its combination of earthiness and elegance, agate is one of the most unusual gemstones. There are many varieties of agate, including blue lace agate, moss agate, tree agate and petrified wood.
Blue Lace Agate is a variety of banded Chalcedony, a mineral of the Quartz family. It is usually banded in layers of predominantly light blue, striped with brighter blues, whites, and even brown threads of color.