Shree-yantra is a very rahasyamayee yantra. There are lot of variations like , bhuprustha, kachhappa, merupristha etc.General rule is that shree-yantra should be a big one on precious metal, precious stones,etc. I have seen the shri-yantra change the colour, produce good aroma and giving results.
I have been in touch with a person ( now his body is not with us) who used to do just little pujan , some-mudra and presto the results were there. I have got benefit from him. He was a very kind and pious guru. His working was very strange, in a small room he sit and did all the pujan. Then, we talked on all subjects. There were few persons when i go to their home. Actually he allowed me to touch his shri-yantra and we did pujan. As for knowledge he had very little knowledge of tantra. What he actually did was working. He worked at the ripe age of may be 70. When i met him he was very old person. But see me his eyes become bright. He was a gem. Very few person have that much lineage. He had a good spiritual lineage. His followers were few, actually he was guru, but disguised as palmist, joytishacharya. He did not establish any temple, his guru-bhai did make a big temple and all sort of things, (A big famous temple of nadiad).
His most of benefectors live in USA,UK and other foreign countries. I have seen lot of marriages taking places due his interventions which was not possible in normal circumstances and they all are happy.
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