Places to See Rocks and Minerals

Collecting Samples
Being Safe
Where to look
What to look for

The Peak District offers lots of opportunities to see rocks in a beautiful setting.

In the Dark Peak you can see the rocks change from shale to gritstone as you walk upslope. These are the best of their type and are internationally important. In the White Peak towering limestone cliffs and deep dales are highly valued, as well as rare volcanic sites.

A number of sites have been identified as of special geological interest. These are called RIGS or Regionally Important Geological and Geomorphological Sites. RIGS complement our Sites of Special Scientific Interest and were introduced in 1990. They are chosen by local voluntary groups and aim to:

• protect important sites through awareness in the planning and development process
• provide opportunities for education for amateur and professional earth scientists
• conserve the historical values and beauty of the site as well as its scientific importance

Collecting Samples

When looking at rocks and fossils please remember:

• All rocks belong to the landowner and nothing should be removed without agreement
• Permission must be gained to enter private land and local bye-laws should always be obeyed
• When examining specimens do this using loose materials on the ground or look at the rocks in situ. Do not damage the rocks in any way.
• Avoid disturbance to wildlife and do not leave the site in an untidy condition.

Make notes of interesting finds. Good record keeping is important so that should something be found that may be of key scientific interest, experts at the local museums can be informed

And don't forget the Country Code!

Being Safe

Use the following guide to keep safe:

• keep to marked paths
• be prepared for Peak District weather
• use a map to find your way there - and back!
• watch out for loose rocks and wear a hard hat near steep rock faces
• be careful walking on scree slopes and over loose rocks and boulders
• there are lots of old mine shafts in the Peak District, even capped shafts should be treated with care
• ask an expert caver/guide to accompany you on visits to old workings or caves

What to Look For

It is possible to identify many Peak District's rocks and minerals by simply looking carefully and describing a sample (please go to collecting rock samples before you begin).

The following questions will help but a good field guide is invaluable:

1. Location - are you in the White Peak, South-West Peak or Dark Peak?

2. Rock face - are there signs of bedding or any different rocks above or below it?

3. Take a closer look - find a small sample on the ground around the rock face (please replace it afterwards) or look at the rock face itself (you must not use a hammer to remove a piece).

Always look at a fresh surface if possible and examine it carefully with a hand lens or magnifying glass. Then try to answer these questions:

• What colour is it?
• Can you see individual grains, if so what is their size and shape? Or does the rock look fused and crystalline?
• Can you spot any fossils?
• How does the rock break and is it capable of splitting?
• Is there a clear crystal shape?
• Feel the texture, is it rough or smooth?
• Compare your sample’s weight to a different sample of the same size. Is it unusually heavy or light?
• Use a knife to test how hard it is and compare to Moh’s scale of hardness

4. Think about what it can’t be, for example there are no fossils in lava. Check your answers with the simple table below or a field guide.

Typical Peak District Rocks and Minerals

ROCK	COLOUR	TEXTURE	GRAIN SIZE	FRACTURE	FOSSILS	IMAGE
BASALT	dark blueish or dark red, weathers red or greenish	dense, smooth, ropy or with (filled) vesicles	crystalline or fine	broken surface dull	no
DOLERITE	dark blueish, weathers to brown	smooth or ophitic (large crystal encloses smaller)	crystalline, medium	-	no
LIMESTONE	white, grey, cream when pure, darker when impure	variable from smooth to crystalline, sugary and fossiliferous	fine	-	yes
MUDSTONE	grey, black, brown	very smooth	very fine, indistinguishable to naked eye	-	yes
SHALE	grey, black	very smooth	very fine, indistinguishable to naked eye	splits easily into thin layers	yes
SANDSTONE	very variable often red/brown, yellow	rough, individual grains may be rubbed off	medium grained, well sorted, often rounded and of same size – easily seen	may crumble if weathered	yes
GRITSTONE (COARSE SANDSTONE)	very variable often red/brown, yellow	very rough, individual grains may be rubbed off	Medium to large, often angular and of different sizes	may crumble if weathered	yes

MINERAL	HARDNESS	CRYSTAL SHAPE	WEIGHT	IMAGE
CALCITE	3 – scratches easily with knife	scalenohedra but varies widely, ‘nail-head’ spar common	specific gravity 2.7
FLOURITE (FLOURSPAR – BLUE JOHN)	4 – scratches easily with knife, can mark calcite	cubic, cubes often packed together in twins or as bands to give fibrous appearance	Specific gravity 3.2
QUARTZ	7 – scratches glass, cannot be scratched with knife	six-sided prisms topped by six-sided prisms	specific gravity 2.65
PYRITE (FOOL’S GOLD)	6-6.5 – sparks when struck sharply	Cubic, massive, spheroidal, radiating	specific gravity 4.9-5.2
BARITE (HEAVY-SPAR)	2.5-3.5 – scratches easily with knife	Tabular, fibrous, cockscomb, rosette-like or massive	specific gravity 4.3-4.6 – feels heavy
GALENA	2.5 – quite soft	Cubes common or octahedral (cubes with missing corners)	7.4-7.6 – sample with lead inside will be very heavy

Specimens photographed with kind permission of Buxton Museums & Art Galleries