Gold is always a treasure no matter the size

Last weekend, I visited the Jiu fen Gold ecological Park, New Taipei City (Taipei County)'s. As this park shows, old mining facilities can be transformed into a premier recreational tour attraction with many of the park’s original buildings being re-used as exhibition and tourist destination. The main buildings of the park includes the Museum of Gold, environmental building displaying natural environment and geology around Jinguashi area, Gold-refining building offers opportunities for tourists to filter gold from minerals through water, Crown Prince Chalet for a glimpse of an elegant Japanese palace style building, Four Joined of Japanese –style residence for high level employees as a living house, Benshan Fifth Tunnel giving visitors a taste of what it was like to work down the mine and a Tourist information center. The best time I had was, I got chance to touch a 250 kg of gold inside the museum. Guess how much the price of this gold??

Figure 1. 250 kg gold inside the Gold museum in Jiufen

Gold (Au) which come from Latin name as Aurum, , (scientific reason: they are inert to Oxygen) won't far away from human civilization history. Gold are important motivation for adventure or even conflict. Every civilization around the world have countless tale about the gold starting from 4000 BC when the Egyptian force the prisoners war to dig the soil for searching the gold, Qin dynasty which make gold as a wealthy symbol and also accepted currency, or the Marcopolo’s journey to find a land of gold until gold rush in United State on 19th century and continue spread to the world. From time to time, gold was never loss their values.

Anyway, I won't talk about the story about the bulk gold . Gold is always gold; no matter how much is the size. Have you seen or heard about medieval stained glass artisans? Do you believe that has made by gold?? Yeah it's gold only the matter they are in very tiny size. The first nanotechnologists, as they, although unaware, trapped gold nanoparticles in the 'glass matrix' in order to generate the ruby red color in the windows. When the metal such gold turn into very small size (as big as virus), actually they will have a very different properties from their bulk.

Figure 2. Gold and silver nano-particles give stained glass its pigmentation

The enchantment of Au NPs since ancient times, as reflected in their intense color, originates from the basic photophysical response that does not exist to nonmetallic particles. When a metal particle is exposed to light, the oscillating electromagnetic field of the light induces a collective coherent oscillation of the free electrons (conduction band electrons) of the metal. This electron oscillation around the particle surface causes a charge separation with respect to the ionic lattice, forming a dipole oscillation along the direction of the electric field of the light (Fig. 1A). The amplitude of the oscillation reaches maximum at a specific frequency, called surface Plasmon resonance (SPR). The SPR band intensity and wavelength depends on some factors such as the metal type, particle size, shape, structure, composition and the dielectric constant of the surrounding medium.

Figure 3. Ilustration of Surface Plasmon Resonance of Gold

So what the future of this tiny treasure??

Gold nanoparticles are being tested as components in technology and medicines. You can see in this video how the tiny treasure of gold could be used to kill cancer cells, improve the efficiency of solar cells and catalyze chemical reactions.