10x – A Cadmium metal button, which is nearly as white as silver and Indium.

20x – A fragment of flattened Cadmium Metal being dissolved in 1 drop HNO3 and 2 drops H2O.When a little heat is applied to hasten the dissolving action of the HNO3 the rising vapors have the odor of coffee.
The crystal grain boundaries resemble silver as better illustrated in next image.

40x – A magnified view of a portion of the preceding image, attempting to focus upon the grain boundaries that resemble silver in similar circumstances.

25x – The preceding digestion is complete and a little heat applied to hasten the drying process, which produced this crystalline formation of Cadmium in a nitric acid solution.

This dried supersaturated crystalline deposit may or may not be helpful in identifying Cd if other elements are present.

10x – 1 drop of water and 1 drop of HNO3 was applied to the preceding imaged dried solution and a single crystal of K2CrO7 (potassium dichromate) was inserted.
No immediate precipitant formed. Nor after 30 minutes was there a precipitant.
I would not consider K2Cr2O7 a reagent to use for identifying Cd in a nitric acid solution.

The next 2 images show what happens when a little heat is applied to this solution.

10x – As heat was applied to the HNO3 solution the K2Cr2O7 crystal dissolved and these yellow crystals began growing.

25x – A magnified view of the preceding image to better illustrate the structure of the crystalline formations.
When heat from the cigareet lighter flame was gently applied to underside of the glass slide there was a acid reaction indicated by the air bubbles, which has a slight tint of green and is likely chrome liberated from the K2Cr2O7.
Again, I would not consider this yellow crystal formation as a reliable guide in identifying Cd in a nitric acid (HNO3) solution.

10x – A piece of Cd was dissolved in 1 drop HNO3 & 1 drop H2O.
The solution was further diluted with 3 more drops of water to avoid an undesirable reaction with potassium Iodide. Then a crystal of KI was inserted into this solution and an immediate yellow color formed, but no precipitate formed.

NOTE: Cd vigorously dissolves in concentrated HNO3 with the evolution of copious amounts of reddish nitrous oxide fumes.

10x – Because no precipitant formed and being impatient the glass slide was heated to initiate some sort of reaction, which this image indicates with this black deposition.

40x – This black precipitate resembled reduce Iodine crystals due to reacting with HNO3. However, upon further heating no reaction formed and these black crystals dissolved, which I have not seen occur before. Normally, too much heat will initiate a reaction between the Iodide and HNO3.
It entirely possible that this precipitation is a significant aid in determining the presence of Cd in diluted HNO3.

10x – This is the dried solution from preceding image containing HNO3, H2O, dissolved Cd and KI, which seemed to precipitate the black crystals that dissolved and formed this image of the dried solution.
I repeated this microchem a couple more times with nearly identical results. Yet, I remain unsure about this result and whether or not KI is a suitable reagent in HNO3 to determine the presence of Cd in this type of solution.

The next 6 images are solutions that concentrated HCl was utilized.

10x – A piece of Cadmium metal that was subject to 1 drop of HCl and gently heated to dry, which produced this white and tinge of blue super-saturated deposit rings.

HCl does not dissolve Cadmium metal as easily nor as quickly as HNO3 does. In fact HCl is quite slow and needs a little heat to dissolve this metal.

10x – A single crystal of K2Cr2O7 was inserted in the HCl solution containing the amount of dissolved Cadmium in preceding image.
There was no immediate precipitant, but a orange-yellow color formed as the potassium dichromate began to dissolve.

10x – The K2Cr2O7 crystal has dissolved, but no precipitant formed, so heat was applied to the glass slide, which formed this deposition when heat was applied to cause super-saturation.

30x – A magnified view of the lower right corner of the preceding image that better illustrates the near dry saturated crystalline structures that K2Cr2O7 helped create.

40x – A magnified view of the preceding image.
The heated to near dry crystalline deposition is beginning to re-liquefy by pulling moisture from the room air.

I would not consider K2Cr2O7 as a reagent to determine the presence of Cadmium in a HCl solution. However, potassium dichromate would be beneficial to identify other metals in chemical combination with dissolved Cadmium.

10x – Another HCl solution that has digested another fragment of Cadmium metal.
This image illustrates the effects of the insertion of a ammonium chloride crystal.
Although the ammonium chloride cause no precipitant to form when the solution was brought to this near dry condition there formed these unique white crystals on the outer perimeter.
These white unique crystals, plus the hints of a light blue color may be a useful in determining the presence of Cadmium if other elements were present in the HCl solution. However, because there was no precipitation I would not reply on these results.
This image was only added so provide another perspective and it is apparent that a variety of other reagents are required to be used to determine which reagents is the most useful to determine Cadmium in this type of HCl solution.

10x – This toothpick tip was inserted in the acidic solution containing the dissolved Cadmium and ignited.
No metal was reduced.
There is a white fluffy end, which is associated with the burnt orange area.

40x – This magnified view of the reignited preceding image and still no metal reduced.

40x – A magnified view of the preceding image, which was again ignited, but no metal was reduced.