This EarthCache is not mean to be difficult, it is meant to be interesting, without worry of the need to provide answers which make you feel you are completing a thesis for a Masters Degree 
. The co-ordinates take you to the paved area at the immediate front of the Margaret McMillan Tower in Bradford. Quite fitting that the name McMillan is related to here, an ancient Highland clan, well the stone that you stand on also comes from the land to the north of the wall (Hadrians that is), Scotland.
So what are we here to look at, well look down, what you are stood on is known as Gneiss. Gneiss is what is known as metamorphic rock, this means it started off in different form, then heat and pressure caused it to change, in other words it transformed. Gneiss is characterized by banding, this is caused by the protolith being stretched, and the original compenents making it up being seperated into sheets, which can be seen as bands.
So lets go back to the past, to a time long before Robert the Bruce, Bonnie Prince Charlie, Dalradia and the Picts.
At first it started off as either a igneous rock, or a sedimentary rock (there are plenty of EarthCaches which describe these), which was then transformed through the action of pressure and heat. A gneiss formed originally from igneous rock is known as orthogneiss, that which that formed from a sedimentary rock is known as paragneiss. The original rock is known as the protolith.
There two types of metamorphic processes:
(1) Contact metamorphism, in this case rocks that are so close to magma, that they start to partially melt, and change their properties. Temperature is the main driver here.
(2) Regional metamorphism, this happens when rocks are deep underground and are subjected to massive pressures, which causes them to become elongated, and the original features are destroyed. Pressure (often times with temperature) is the main driver here.
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Foliation and Non Foliation.
Metamorphic rocks can have crystals and minerals from the original rock, as well as new minerals resulting from the process of metamorphism. Changes in the chemical environment can also occur, either as mechanical dislocation, where the rock and /or some minerals are physically altered, and chemical recrystallisation, which is when temperature and pressure cause some crystals to change into other crystals.
These processes can cause what is known as Foliation or Non Foliation.
Foliation, is where the metamorphic processes squeezes and elongates the crystals forming the rock, and clear defined aligment can be seen, in laymans language it means you can see defined lines.
Non Foliation is where there is no clear alignment, i.e there are non defined lines.
This being an EarthCache, in order to log it, I ask that you complete the below tasks. Please send the answers 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. Between the steps and the door, there is a distinctly banded slab of gneiss, please describe the structure of the gneiss here, by this I mean the colours, how wide any bands are, what shape they are, and are they straight or wavy.
2. Is the Gneiss foliated or non foliated, please explain your rationale.