26–50
No.26
Super 4
Glen Clova, Angus
St zone
xpl 2 mm
xpl 2 mm
ppl 2 mm
xpl 2 mm
xpl 2 mm
ppl 1 mm
Sericite → Chl (?)
xpl 1 mm
ppl 1 mm
xpl 1 mm
Some reaction between the upper Grt & the neighbouring Bt (?)
xpl 1 mm
Chl between the two Grt grains
ppl 2 mm
Retrogression of Tur
xpl 2 mm
ppl 2 mm
Tur → Chl
xpl 2 mm
ppl 2 mm
xpl 2 mm
ppl 8 mm
xpl 8 mm
No.27
SS P2
Qz-Mica schist
Loch Leven, Argyll [below HBF]
Bt zone
ppl 8 mm
xpl 8 mm
ppl 2 mm
xpl 2 mm
xpl 2 mm
ppl 1 mm
xpl 1 mm
xpl 1 mm
No.28
SS N11
Sil-Grt-Mica schist
Glen Clova, Forfar
Sil zone
ppl 2 mm
Ky ?
xpl 2 mm
(The grains have inclined extinction)
ppl 1 mm
St
xpl 1 mm
Accessory Czo in SW
ppl 2 mm
Lamellar twins picked out by sericitisation
xpl 2 mm
xpl 2 mm
ppl 8 mm
xpl 8 mm
ppl 2 mm
xpl 2 mm
ppl 2 mm
xpl 2 mm
ppl 2 mm
Needles inside Qz
xpl 2 mm
ppl 1 mm
xpl 1 mm
No.29
SS N10
Sil-Ky-Grt schist
Glen Clova, Forfar
Sil zone
ppl 8 mm
xpl 8 mm
xpl 8 mm
ppl 2 mm
xpl 2 mm
Undulose extinction
xpl 2 mm
ppl 8 mm
xpl 8 mm
Simple twin
xpl 8 mm
ppl 2 mm
Pleochroic halo in Bt
xpl 2 mm
xpl 2 mm
No.30
Z10.29
Bt-St schist
Whitehills Harbour
St zone (Buchan)
ppl 2 mm
xpl 2 mm
ppl 1 mm
St
xpl 1 mm
ppl 8 mm
xpl 8 mm
xpl 8 mm
ppl 1 mm
xpl 1 mm
xpl 1 mm
ppl 1 mm
xpl 1 mm
ppl 1 mm
xpl 1 mm
ppl 1 mm
xpl 1 mm
ppl 2 mm
xpl 2 mm
No.31
Z8.B3
Macduff Slate
Chl zone (Buchan)
ppl 8 mm
xpl 8 mm
Layers of different grain sizes
No.32
Z9.26
Macduff Slate
Bt zone (Buchan)
ppl 8 mm
xpl 8 mm
ppl 8 mm
xpl 8 mm
ppl 2 mm
xpl 2 mm
No.33
12.33
Sil gneiss
Cowhythe Bay
Sil zone
ppl 2 mm
xpl 2 mm
Intergrowths
ppl 8 mm
xpl 8 mm
Simple twin
xpl 8 mm
xpl 8 mm
ppl 1 mm
xpl 1 mm
Pinched-out polysynthetic twins
ppl 2 mm
xpl 2 mm
ppl 2 mm
xpl 2 mm
ppl 2 mm
xpl 2 mm
Symplectites (& a hole in the centre ?)
ppl 1 mm
ppl 1 mm
Tur (?)
xpl 1 mm
Straight extinction
xpl 1 mm
(It was length fast)
ppl 1 mm
Bt → Chl below centre
xpl 1 mm
Sericitisation
No.34
G163
Or-Crd-Spl hornfels
1 mile NE of Comrie, Perthshire
Bt zone
ppl 5 mm
xpl 5 mm
ppl 1 mm
xpl 1 mm
Symplectite
ppl 5 mm
xpl 5 mm
With a filter...
ppl 5 mm
xpl 5 mm
With a filter...
ppl 2 mm
xpl 2 mm
ppl 5 mm
xpl 5 mm
xpl 2 mm
ppl 2 mm
xpl 2 mm
ppl 2 mm
xpl 2 mm
xpl 2 mm
ppl 2 mm
ppl 1 mm
xpl 1 mm
(Video)
xpl 1 mm
Three symplectites
No.35
G260
And-Bt schist
Sandhaven Grampian
And zone
ppl 2 mm
Moderate-high relief
xpl 2 mm
And (?)
xpl 2 mm
Extinction position
ppl 5 mm
Coarser grains at the edge
xpl 5 mm
Extinct all as one
xpl 5 mm
ppl 1 mm
Hexagonal accessory: Ap
ppl 2 mm
xpl 2 mm
Essentially isotropic
No.36
G259(i)
St-Grt schist
Portlethen, Aberdeenshire
Sil zone
ppl 5 mm
xpl 5 mm
ppl 5 mm
St → Chl
xpl 5 mm
No.37
G177(i)
Sil-Grt-Mca schist
Western side of Loch Brandy, Glen Clova
Sil zone
ppl 5 mm
xpl 5 mm
No.38
G309
Qz-Ab-Chl-Ms schist (some Cal)
1 m NE of Tarbet, Loch Lomond
Chl zone
ppl 1 mm
xpl 1 mm
Poikilitic Pl
ppl 5 mm
xpl 5 mm
ppl 2 mm
xpl 2 mm
Kind of complicated extinction pattern
xpl 2 mm
No.39
G100
(Quartzite)
ppl 5 mm
xpl 5 mm
Ep N of centre
No.40
G167
Qz-Grt-Mca schist
Craigs of Lethnot, Glen Clova
Grt zone
ppl 5 mm
xpl 5 mm
ppl 2 mm
xpl 2 mm
Zrn?
ppl 1 mm
xpl 1 mm
Zrn?
No.41
G168
Grt-Bt schist (with most of the Bt retrograde to Chl, and much Fsp, presumably Ab)
Lower slopes of Elf Hillock, Glen Clova, Angus
Grt zone
ppl 5 mm
xpl 5 mm
No.42
G171
St-Bt schist
NE slopes of Craigs of Inchdowrie, Glen Clova
Ky zone
ppl 2 mm
St to the SSE
xpl 2 mm
Ms → Chl
ppl 2 mm
xpl 2 mm
Ky in the centre (simple twin)
xpl 1 mm
No.43
G207
Migmatite
S side of Nigg Bay, Aberdeen
Sil zone
ppl 5 mm
xpl 5 mm
Kfs
ppl 5 mm
xpl 5 mm
Kfs and fibrolite (Sil)
ppl 1 mm
xpl 1 mm
Symplectite (inside a Kfs grain)
No.44
G505
Qz-Pl-Grt-Bt gneiss
R. Devron, near Huntly, Aberdeenshire
Sil zone
ppl 5 mm
Grt, Bt, Qz, & Sil (fibrolite)
xpl 5 mm
ppl 5 mm
xpl 5 mm
The rod-like, low-birefringence phase partially encases some grains
ppl 2 mm
St grain to E
xpl 2 mm
Geode-like pattern in centre (most likely a hole in the section)
ppl 2 mm
Pale green rods. Yellow pleochroic halo SW of centre
xpl 2 mm
Very low birefringence inclusions in Crd
xpl 2 mm
No.45
G195
Ky-Grt-Qz-Mca schist
N slopes of Carn Mor
Ky or Sil zone
ppl 2 mm
xpl 2 mm
ppl 2 mm
Ky(!!)
xpl 2 mm
ppl 5 mm
Ms & Gr fingerprint pattern
xpl 5 mm
Bright pink prismatic grain
xpl 5 mm
Straight extinction
ppl 2 mm
xpl 2 mm
(Length slow)
ppl 2 mm
High relief, one good set of cleavage
xpl 2 mm
xpl 2 mm
Straight extinction
ppl 5 mm
xpl 5 mm
Lots of Ky
ppl 2 mm
Grt to the east
xpl 2 mm
Sericite
xpl 2 mm
No.46
G149
Crd-Or-Bt-Crn-Spl hornfels
Tom a'Mhinn, Glen Lednock, Perthshire
Crd zone
ppl 2 mm
Colourless high relief: Crn
Green high relief: Spl?
xpl 2 mm
ppl 0.5 mm
No pleochroic halo
ppl 0.5 mm
Pale yellow pleochroic halo in centre
xpl 0.5 mm
High birefringence Ep in Crd
ppl 1 mm
ppl 1 mm
Zoomed-out pleochroic halo in centre
No.47
G161
Bt-Chl-Qz hornfels
Aberfoyle Slates, S. of Craig More (158 m), N of Comrie
Bt zone
ppl 5 mm
xpl 5 mm
Ep in SE (bright pink birefringence)
No.48
G202
Spotted And-Crd hornfels
Western slopes of Red Hill Insch, Aberdeenshire
And zone
ppl 1 mm
Squares
xpl 1 mm
ppl 2 mm
xpl 2 mm
Crd in centre (sector trilling)
xpl 2 mm
ppl 5 mm
xpl 5 mm
ppl 2 mm
xpl 2 mm
xpl 2 mm
With sensitive tint
Central blue elongate And (length fast)
Crd NE of centre (sector trilling)
No.49
G204
ppl 5 mm
xpl 5 mm
No.50
G184
Qz-Mca schist (a little Grt)
Below bridge over the Allt Ionndrain [?], Glen Roy
Grt zone
ppl 5 mm
xpl 5 mm
Sharp crenulation
ppl 2 mm
xpl 2 mm
Inclusion-rich Grt
ppl 1 mm
xpl 1 mm
xpl 0.5 mm
Ep and Czo