Section_grinding

薄片研磨　その１．機械摺り

Most impotant part of thin-section making process.

The process is recemble to tip grinding, but some details are different.
This stage is the most important stage in the whole process to make good thin-sections!

At First: The machinery stage:
最初に機械を用いた摺り

Second Stage:The hand stage is the next page->
２番めの手による研磨は次のページ

#180 Grinding; until the section turns transparent around 0.1-0.3mm thickness,
#180 の摺り：薄片の厚さが 0.1-0.3mmで岩石が透明になるまで摺る．

Next Video, a Gabbro section,
次の動画ははんれい岩の薄片

The section color changes lighter.
The thickness: 2.35mm to 1,48mm at 2min. Average rate is 0.44mm/min
薄片の色がしだいに薄くなる．上記ビデオでは２分間で 2.35mm から 1,48mm に減っている．１分で0.44mm減った勘定になる．

Another video, an Andesite section,
別の動画で安山岩の薄片

This video shows a little bit thick section about 3.81mm(-1.3mm = 2.5mm is the actual thickness of rock)
The thickness decrease 2.5mm to 0.3-0.4mm during 2.5 min.
So, the grinding rate is around 0.9mm/min.
This rate is the mean value from my experiences.
これはかなり厚い薄片．石の厚さが2.5mmほどある．２分半で 2.5mm が 0.3-0.4mm まで減った．
この減り方は私の経験から言ってほぼ平均の値．

The image shows the difference between before and after #180 grinding.
この写真は#180の前とあとでの違いを示す．

After #180, Kannabe Basalts, numbers are thickness of sections (glass thickness are 1,27-1,29mm) ：the thicknesses are measured by a digital caliper. Samples are basalts at Kitatajima
これは#180のあとの状態で，写真の数字はそれぞれの薄片の厚み（1,27-1,29mm厚のガラスを含む）を示す．なお厚みは上の写真のデジタルゲージで測定．サンプルは北但馬の玄武岩．

Next;
#320 Grinding
次は#320の摺り．

This video shows: thickness 1.5mm reduces to 1.33mm (actually 0.2mm to 0.03mm) during 1.5min.
It means the grinding rate is 0.11mm/min. The #320 has a mild grinding rate than #180.
Also, You can see the color of section turns to transparently.
この動画は１分半の時間で，1.5mm の薄片が 1.33mm に減っている（石本体の厚みは 0.2mm が 0.03mmに減る）．

Another example, Diorite,
他の例として閃緑岩

After finishing with homemade Grinder #180 to #320
The numbers show after section-cutting, #180 and #320, descending order. measuring with a digital caliper including glass and glue.

Next Stage -->