coal ball उदाहरण वाक्य
उदाहरण वाक्य
- The best known callistophyte was documented from Late Pennsylvanian coal ball petrifactions in North America.
- Thin sectioning was an early procedure used to analyse fossilised material contained in coal balls.
- After applying acetone, a piece of cellulose acetate is placed on the coal ball.
- It was not until 1922 that coal balls were discovered and identified in North America.
- Coalification was thus prevented, and the peat was preserved and eventually became a coal ball.
- North American coal balls are more widespread, both stratigraphically and geologically, than those in Europe.
- Coal balls are not made of coal; they are non-flammable and useless for fuel.
- Chitaley's revisions begin after grinding the surface of the coal ball to a smooth finish.
- David Watson analysed coal ball samples and decided that coal balls formed " in situ ".
- David Watson analysed coal ball samples and decided that coal balls formed " in situ ".