Picture is an example, (stones sold individually) shapes and color may vary somewhat
They help obtain a better physical or emotional balance. They work to raise consciousness. Builds self-confidence. This is Chalcedony Quartz. Red, orange, yellow, browns: Solid, Grounding. For stomach, colon, liver, spleen, kidneys. Centering, taking heart. Blood sugar, anorexia or food issues, lymph nodes, Balances emotions. Insight, Restores nerve feeling and healing after injury or burns. Gaze into for meditation. Left/Right brain balance. Pineal, pituitary; coordination. Patience, peace. Cools 
Agates foster love, abundance, wealth, good luck, longevity, acceptance, courage, protection, balance, harmony, generosity, strength, security and appreciation of nature. Agates are considered very powerful stones. They are also very calming and soothing to the emotions.
Agate is a banded, concentric shell-like chalcedony, sometimes containing opal substance. The fine quartz fibers are oriented vertically to the surface of the individual band layers. The bands can be multicolored or of the same color. 

The agates of the exhausted German mines had soft to strong colors (especially pink, red, or brownish) and were separated by bright gray bands. The South American agates are mostly dull gray and without special markings; only through dyeing do they receive their lively colors. Transparency of agates varies from nearly transparent to opaque. In thin slabs, even the opaque agates are mostly translucent.