We have been looking at leaves at HomeLabs.
First we cleared the soft tissue of a Peepul leaf by soaking it in water for 4 weeks. The soft tissue decomposes in those 4 weeks and easily comes off on brushing the leaf. What remains are the leaf veins. The lignin in the leaf veins does not decompose easily. These leaf veins transport food and water to the leaf and provides mechanical support to it.
The video of how we made these leaves is shown below. Above is a Peepul leaf skeleton at 20x magnification on a white background. And below is the same leaf on a black background. We used a USB microscope for this that we had bought for about $75.