On an indeterminate day in ~ 1996, I collected my first mineral specimen. I was about 6 years old at the time, and like many of my antiquity did not know the difference between a rock and a mineral. So I called my fledgling collection a rock collection and it came to be called a rock collection.
12 years later, I had the pleasure of answering firmly in the affirmative when a couple of unlucky moving company workers asked of the (moderately heavy) boxes they carried to my new home in Bangalore: "What do you have in here, rocks?!"
10 years further on, and I'm moving house again. Unfortunately, my rock collection couldn't come along this time and I'm not certain when I'll next see it.
If that last line sounded to you like it was dunked in a deliciously warm mug of emotion, you're right. People become geologists for all kinds of reasons. Among my geologist acquaintances are those who embarked down that rocky road because of the allure of the oil industry, those whose first career choice in medicine or engineering failed, and even a few who took it up simply because it was "something different" in an engineering obsessed country. The driving force behind my decision to study geology was an almost irrational fascination about the Earth and its products, a desire itself rooted in the beautiful mineral and rock specimens that occupied my home for so long.
I thought I'd write a little about my collection of rocks, far away as it is now, as a means of reliving the moments when I collected them. My rock collection is more than a few quartz, zeolite, fossil, ore, and rock specimens. My collection of rocks is a collection of memories.
Blue Chalcedony
Chalcedony is a kind of quartz. Made up of crystals, tiny and numerous, chalcedony is given the quaint yet now modern sounding descriptor "cryptocrystalline". Called agate or onyx when banded, or carnelian, chrysophrase, or sardonyx when coloured, chalcedony represents the triumph of nucleation over growth, the two processes that compete to create crystals. On a blazing summers day in 1998 Nashik, I trekked up Ramshej Fort to see Long-Billed Vultures nest. Somewhere along the way a glint of blue caught my eye, and I wiped away the mud on a boulder to reveal a vein of bright blue chalcedony. My poor father, who happened to be with me at the time, soon found himself on his knees, chipping away at the vein with a piece of basalt I had helpfully commandeered for him. This would not be the first time he did something like this. Some time later, I held the specimen up to the light and marvelled at its colour. The colour of minerals is what attracted me to them in the first place, led me to collect and study them as an amateur, and ultimately write my master's thesis on them.
Colourless Apophyllite
There is no dearth of dirty jokes in the geological sciences given our colourful technical vocabulary. One of my favourite geological terms is cleavage, the property of certain minerals to split along preferred crystallographic planes due to weak bonding. Apophyllite is a silicate mineral in the tetragonal crystal system that displays stunning basal (or pinacoidal if you like even fancier terms) cleavage, meaning that its crystals tends to break, quite easily, in directions parallel to their bases. Before I knew what cleavage was (mineralogical, or well, the other kind), I was fascinated by the razor thin reflective surfaces I saw in apophyllite crystals. My great uncle, a retired GSI geologist and one of my inspirations to take up geology, bequeathed unto me a pocket lens that I used to gaze deep into my apophyllite crystals. On one such occasion, carelessness led to the crystal slipping from my grasp and falling to the floor, splitting in two along the surface my eye was so keen to study. In my first ever mineralogy class as an undergrad, I learned what that surface was, why the crystal broke along it, and that one of the signs of a seasoned geologist is the ability to resist chuckling when someone says "cleavage" in class.
Pelitic Granulite
In 2011, I visited the South Delhi Fold Belt for three weeks of geological fieldwork. The fact that we were in Gujarat, a famously "dry" state, meant that we actually had to work instead of indulging in bottled pleasure every evening the way most respectable geologists do. On one of our traverses, we came across a massive outcrop of pelitic granulite, remnants of shale that had been buried deep in the Earth's crust, metamorphosed, and finally exhumed in a shiny, banded avatar. The granulite, with its pink leucosome bands and black melanosome bands, would look perfect in my display cabinet and so I set out to collect a sample with my trusty Estwing E320. Now, as someone accustomed to working in basaltic terrain with only minor exposure to metamorphic rocks, I hadn't a clue about how hard these rocks really were: something I was soon to discover at the expense of my hands which were bloodied and bruised by the time I had collected a reasonably sized sample. On this occasion, the term "hand-specimen" as used by many a geologist, could apply just as easily to the granulite I had laboriously extricated from the rock mass as it could to my own appendages that were red, swollen, and covered in all manners of cuts and bruises.
......
To be continued...
12 years later, I had the pleasure of answering firmly in the affirmative when a couple of unlucky moving company workers asked of the (moderately heavy) boxes they carried to my new home in Bangalore: "What do you have in here, rocks?!"
10 years further on, and I'm moving house again. Unfortunately, my rock collection couldn't come along this time and I'm not certain when I'll next see it.
If that last line sounded to you like it was dunked in a deliciously warm mug of emotion, you're right. People become geologists for all kinds of reasons. Among my geologist acquaintances are those who embarked down that rocky road because of the allure of the oil industry, those whose first career choice in medicine or engineering failed, and even a few who took it up simply because it was "something different" in an engineering obsessed country. The driving force behind my decision to study geology was an almost irrational fascination about the Earth and its products, a desire itself rooted in the beautiful mineral and rock specimens that occupied my home for so long.
I thought I'd write a little about my collection of rocks, far away as it is now, as a means of reliving the moments when I collected them. My rock collection is more than a few quartz, zeolite, fossil, ore, and rock specimens. My collection of rocks is a collection of memories.
Blue Chalcedony
Chalcedony is a kind of quartz. Made up of crystals, tiny and numerous, chalcedony is given the quaint yet now modern sounding descriptor "cryptocrystalline". Called agate or onyx when banded, or carnelian, chrysophrase, or sardonyx when coloured, chalcedony represents the triumph of nucleation over growth, the two processes that compete to create crystals. On a blazing summers day in 1998 Nashik, I trekked up Ramshej Fort to see Long-Billed Vultures nest. Somewhere along the way a glint of blue caught my eye, and I wiped away the mud on a boulder to reveal a vein of bright blue chalcedony. My poor father, who happened to be with me at the time, soon found himself on his knees, chipping away at the vein with a piece of basalt I had helpfully commandeered for him. This would not be the first time he did something like this. Some time later, I held the specimen up to the light and marvelled at its colour. The colour of minerals is what attracted me to them in the first place, led me to collect and study them as an amateur, and ultimately write my master's thesis on them.
Colourless Apophyllite
There is no dearth of dirty jokes in the geological sciences given our colourful technical vocabulary. One of my favourite geological terms is cleavage, the property of certain minerals to split along preferred crystallographic planes due to weak bonding. Apophyllite is a silicate mineral in the tetragonal crystal system that displays stunning basal (or pinacoidal if you like even fancier terms) cleavage, meaning that its crystals tends to break, quite easily, in directions parallel to their bases. Before I knew what cleavage was (mineralogical, or well, the other kind), I was fascinated by the razor thin reflective surfaces I saw in apophyllite crystals. My great uncle, a retired GSI geologist and one of my inspirations to take up geology, bequeathed unto me a pocket lens that I used to gaze deep into my apophyllite crystals. On one such occasion, carelessness led to the crystal slipping from my grasp and falling to the floor, splitting in two along the surface my eye was so keen to study. In my first ever mineralogy class as an undergrad, I learned what that surface was, why the crystal broke along it, and that one of the signs of a seasoned geologist is the ability to resist chuckling when someone says "cleavage" in class.
Pelitic Granulite
In 2011, I visited the South Delhi Fold Belt for three weeks of geological fieldwork. The fact that we were in Gujarat, a famously "dry" state, meant that we actually had to work instead of indulging in bottled pleasure every evening the way most respectable geologists do. On one of our traverses, we came across a massive outcrop of pelitic granulite, remnants of shale that had been buried deep in the Earth's crust, metamorphosed, and finally exhumed in a shiny, banded avatar. The granulite, with its pink leucosome bands and black melanosome bands, would look perfect in my display cabinet and so I set out to collect a sample with my trusty Estwing E320. Now, as someone accustomed to working in basaltic terrain with only minor exposure to metamorphic rocks, I hadn't a clue about how hard these rocks really were: something I was soon to discover at the expense of my hands which were bloodied and bruised by the time I had collected a reasonably sized sample. On this occasion, the term "hand-specimen" as used by many a geologist, could apply just as easily to the granulite I had laboriously extricated from the rock mass as it could to my own appendages that were red, swollen, and covered in all manners of cuts and bruises.
......
To be continued...
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