When we are making use of a metallic object, we are not necessarily thinking about how the metal was extracted from its ore. Even if we do remember that the atoms that make up the metal object in question were once likely combined with oxygen or sulfur in a brittle (if not also hard) material, we might not take time to reflect on the beauty of the mineral forms. Yet taking the time to appreciate the natural world is beneficial to us as both simple humans and as people who work in a technology-influenced environment.

The EDS can detect nitrogen (N), present in many cleaners; as well as carbon (present in many oils); oxygen (usually not terribly informative because it is in rust, some oils and many industrial grinding media); silicon (Si); and aluminum (Al), which can be present as abrasive residue or “dirt.” EDS can’t detect hydrogen (H), helium (He) or lithium (Li).

Common substances that I find on stamped or machined parts are lubricants, cleaners and rust inhibitors. I do also sometimes find rust. But neither FTIR nor EDS can produce a firm diagnosis of “rust.” That’s because FTIR works best on carbon-based molecules, not ionic compounds (e.g., rust).

As a local heat treater told me years ago, heat treating is great, but only do it when you need to. Because heat treating does not generally make the parts prettier or straighter.

Here's the conclusion to Debbie Aliya's series on a tooth overlay procedure.

On the subject of tooth damage, many of my teeth have gum-line grooves. A friend who is a retired dental technician insisted that gum-line grooves are a result of brushing horizontally and using an excessively hard toothbrush.

Looking closely at an object and noticing its features and details is a good way to increase our creative powers. Following up on our curiosity is a good way to build a solid foundation of knowledge. Studying natural objects in this way is an excellent entrance to the world of scientific facts.

After the X-ray seen in Figure 1 (see part 1), they put a little optical camera (pediatric size, for which I was grateful) in my mouth to obtain a 3-D digital model of the remaining tooth shape.

Last month, my right rear-lower molar broke. As shown in Figure 1, the fracture event resulted in a chipped condition. The red arrows show the boundary (edge) of the missing piece.

Maybe a half a dozen times in my life I have learned something that, in a minute, totally transformed and rearranged everything I thought I knew about a subject that I thought I had previously understood.