They are both forms of agate. The value of most agate is not all that high. Sometimes pieces from certain places or rare colors command higher prices. There are many, many varieties and colors of agate.
The first pic is a slab from an agate nodule or geode, maybe .50-$1.00
Second pic is slab from what appears to be a stalactite/mite, as noted by EDDE. It is beautiful! A very nice slab! Value? Don't really know! Could be anywhere from $5.00- $15.00+
Thanks every one for the information. I litterally have hundreds of pieces of this type of rock or slabs that I inherited. I sold the saws and grinders. I am not sure what to do with the rocks.
Burdie
The top photo,looks like it could be a "Brazil Agate" They polish up beautiful.If you have alot of those, you could locate a local Rock Shop,or someone who may want to buy the entire slabs you have.Idig.