Talk:Japanese nuclear weapon program/@comment-92.23.238.245-20160325132325

                         Availability of Uranium, Japan 1940-1945.

The following is a translation from the Japanese of the Tonizo report. The author is not recorded but most probably Takeo Yasuda.

       '''On Uranium           Tonizo ( Tokyo No.2 Arsenal ) Laboratory April 1943 '''

                                Extent of deposits in Japan.

Fukushina-ken Date-gun Iizaka mura

Hukuoka-ken Tagawa-gun Yasumaki-mura     1 ton U3O8 100 gm,  ( U3O8 about 90%)

Fukushima-ken  Date-gun Iizaka mura. Salmatos Stone        ( UO2 about 20% )

Gifu-ken Ena-gun Naeki area. Felgson stone           ( UO3 1~2% )

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">                                                                               Ena stone                 ( UO2  11% )

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">Korea………………….. Felgson Stone           UO2 8.4

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">* Manchuria……………                                      Yuukusen stone         UO2 3.8%

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">* is a promising source.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">At present there is no resources found within the East Asian Co-prosperity Sphere.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">                                            ___________________

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">Pre 1940:  East of Shinakawa and Sukagawa, Ishikawaite ( Yuji Shibata & Kenjiro Kimura 1922 )  North of Nakatsugawa, Uranuthorite UO3 9.05%, discovered by H. Awazu 1913.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">Post 1945:  Japan, Ningyo-toge mine 1957-1987  U3O8,  86 ton Uranium/ 86,000 tons ore ie approx. 1%. Would yield about 550 kg U235.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">South Korea, Gwesan, Minwon, Daejon mines.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">North Korea, Cholsen mine etc.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">Manchuria, Lingtou mine etc, Lingtou Provence, Dongbey Region.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">The supply of uranium ore does not appear to have been a limiting factor in Japan’s atomic bomb project. The consignment of 560 Kg said to be on board the German U234 submarine would only have yielded 2.6 Kg of U 235.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">Nishina estimated the critical mass of U 235 as 10 Kg with a reflector but adds “this will not make a bomb, there needs to be extra, another 10 Kg”. Given that 20 Kg of U 235 is needed and the availability of uranium deposits within Japan’s sphere of control, the 2.6 Kg carried in U 234 would have been insignificant.

<p class="MsoNormal"><span style="font-size:12.0pt;line-height:107%;font-family: "TimesNewRoman",serif">The real limiting factor is the scale of the project. In November 1943 Nishina reports that the thermal diffusion tower has yielded an enrichment of 10 % and that a further diffusion tower is in the middle of being built. While theoretically that would have produced bomb grade material, the quantity would have been miniscule.