Just to clarify... the hot bluing job was top notch. I had it done in the US by Precision Bluing. Under natural light or sunlight, the colours look quite even. Under artificial light, especially when photographed, you can quite clearly see the tonal differences. The bolt itself is made of a very hard and durable steel, probably also with a higher nickel content. The bolt handle was likely added by a competent gunsmith after the fact, though there is also evidence to suggest the bolt was "turned down" at the factory as it was a factory option at the time--and delivered partly "in the white". Either way, a brazing alloy was clearly used to join the bolt handle to the bolt body (definitely not low heat silver solder). The bolt handle is also clearly made of a high strength, very hard steel, probably a nickel steel. My inquiry was whether or not a quality old fashioned rust blue would yield better results? It appears, based on some of the responses, yes. Another interesting fact is that the bolt shroud is of the same colour as the bolt handle, and it has its original factory finish. This leads me to believe it is made of the same or similar steel, and also supports the possibility that the bolt handle is a factory original piece. While not shown in the photos, the bolt body itself (under artificial light) also shows a slight progression to a purple-plum hue towards the bolt head. There's a whole lot of nickel going on!