What Hapens to Objects Made of Radioactive Elements as They Decay?

WIKI: diamond+nitrogen

Nitrogen

The most common impurity in diamond is nitrogen, which can comprise up to 1% of a diamond by mass.^[8] Previously, all lattice defects in diamond were thought to be the result of structural anomalies; later research revealed nitrogen to be present in most diamonds and in many different configurations. Most nitrogen enters the diamond lattice as a single atom (i.e. nitrogen-containing molecules dissociate before incorporation), however, molecular nitrogen incorporates into diamond as well.^[10]

Absorption of light and other material properties of diamond are highly dependent upon nitrogen content and aggregation state. Although all aggregate configurations cause absorption in the infrared, diamonds containing aggregated nitrogen are usually colorless, i.e. have little absorption in the visible spectrum.^[2] The four main nitrogen forms are as follows:

C-nitrogen center

C center corresponds to electrically neutral single substitutional nitrogen atoms in the diamond lattice. These are easily seen in electron paramagnetic resonance spectra^[11] (in which they are confusingly called P1 centers). C centers impart a deep yellow to brown color; these diamonds are classed as type Ib and are commonly known as "canary diamonds", which are rare in gem form. Most synthetic diamonds produced by high-pressure high-temperature (HPHT) technique contain a high level of nitrogen in the C form; nitrogen impurity originates from the atmosphere or from the graphite source. One nitrogen atom per 100,000 carbon atoms will produce yellow color.^[12] Because the nitrogen atoms have five available electrons (one more than the carbon atoms they replace), they act as "deep donors"; that is, each substituting nitrogen has an extra electron to donate and forms a donor energy level within the band gap. Light with energy above ~2.2 eV can excite the donor electrons into the conduction band, resulting in the yellow color.^[13]

The C center produces a characteristic infrared absorption spectrum with a sharp peak at 1344 cm^-1 and a broader feature at 1130 cm^-1. Absorption at those peaks is routinely used to measure the concentration of single nitrogen.^[14] Another proposed way, using the UV absorption at ~260 nm, has later been discarded as unreliable.^[13]

Acceptor defects in diamond ionize the fifth nitrogen electron in the C center converting it into C+ center. The latter has a characteristic IR absorption spectrum with a sharp peak at 1332 cm^-1 and broader and weaker peaks at 1115, 1046 and 950 cm^-1.^[15]

A-nitrogen center

The A center is probably the most common defect in natural diamonds. It consists of a neutral nearest-neighbor pair of nitrogen atoms substituting for the carbon atoms. The A center produces UV absorption threshold at ~4 eV (310 nm, i.e. invisible to eye) and thus causes no coloration. Diamond containing nitrogen predominantly in the A form as classed as type IaA.^[16]

The A center is diamagnetic, but if ionized by UV light or deep acceptors, it produces an electron paramagnetic resonance spectrum W24, whose analysis unambiguously proves the N=N structure.^[17]

The A center shows an IR absorption spectrum with no sharp features, which is distinctly different from that of the C or B centers. Its strongest peak at 1282 cm^-1 is routinely used to estimate the nitrogen concentration in the A form.^[18]

B-nitrogen center

There is a general consensus that B center (sometimes called B1) consists of a carbon vacancy surrounded by four nitrogen atoms substituting for carbon atoms.^[2][1][19] This model is consistent with other experimental results, but there is no any direct spectroscopic data corroborating it. Diamonds where most nitrogen forms B centers are rare and are classed as type IaB; most gem diamonds contain a mixture of A and B centers, together with N3 centers.

Similar to the A centers, B centers do not induce color, and no UV or visible absorption can be attributed to the B centers. Early assignment of the N9 absorption system to the B center have been disproven later.^[20] The B center has a characteristic IR absorption spectrum (see the infrared absorption picture above) with a sharp peak at 1332 cm^-1 and a broader feature at 1280 cm^-1. The latter is routinely used to estimate the nitrogen concentration in the B form.^[21]

Note that many optical peaks in diamond accidentally have similar spectral positions, which causes much confusion among gemologists. Spectroscopists use for defect identification the whole spectrum rather than one peak, and consider the history of the growth and processing of individual diamond.^[1][19][2]

N3 nitrogen center

The N3 center consists of three nitrogen atoms surrounding a vacancy. Its concentration is always just a fraction of the A and B centers.^[22] The N3 center is paramagnetic, so its structure is well justified from the analysis of the EPR spectrum P2.^[3] This defect produces a characteristic absorption and luminescence line at 415 nm and thus does not induce color on its own. However, N3 center is always accompanied by the N2 center, having an absorption line at 478 nm (and no luminescence).^[23] As a result, diamonds rich in N3/N2 centers are yellow in color.

So, though it doses not specify, why don't we assume that at leas a part of these Nitrogen are from the decay of the original C₁₄ in the tree or whatever that has transformed into Diamond ?

If your total diamond is of C₁₄ then of course the matter may vbe difficult, First the Nitrogen will go un to C as above. And then the coloured Diamond will become amorphous.