The cache co-ordinates take you to to the side of a bridge next to the canal, you will need to go underneath the arches in order to complete the Earthcache
The bridge is made out of stones and bricks, though what we are interested in is the mortar , or rather what has occured as a result of it. Mortar is traditionally a mix of lime and sand. Lime consists of calcium oxide, gained from heating limestone. At first there would have been neat lines of mortar between the sandstone blocks, but has time has gone on, and the structure has been exposed to water, the calcium oxide reacts with water to form calcium hydroxide. Over time, rainwater carries calcium hydroxide in a solution, which when it comes into contact with air, it reacts with carbon dioxide and calcium carbonate is preciptated.
In a cave the precipitation of calcium carbonate forms both staligtites and staligmites. Though in a location outwith of a cave, these deposits are known as calthemites. A calthemite is a deposit derived from concrete, lime or mortar, and they grow under man made structures, and look like cave structures.
Calthemites can appear in many forms, which are :
Flowstones, which looks like a flowing river off calcium carbonate, this tends to be rippled.
Straw Staligtites, which are long thin straw like structures.
Calthemite staligmites, which are a build up of calcium carbonate on the floor, which gradually gain height.
Calthemite rimstones, these form on the floor as a gradually sloping structure.
When a staligtite and staligmite join, it is known as a column.
Coralloids, these are also known as popcorn. Due to solution evaporation, deposition of calcium carbonate occurs before any drop can form. The resulting coralloids are small and chalky with a cauliflower appearance.
This being an earthcache, in order to log it, I ask that you answer some questions. Please send them to me, and do not include them in your log. You can send them to me by using the message facility or email, both of which can be found by looking at my profile.
1. Please tell me what forms of calthemites you can see.
2. What colour are the calthemites.
3. Is there equal distribution of calthemites throughout the arch? if not, why not?