Thanks for your query.Based on the facts that you have posted it appears that you have
noticed what is called as Agglutination of sperms in your semen which is seen as grains and crystals.
This is most likely to be due to presence of sperm antibodies
in your semen which tends sperms to clump together.
This can be confirmed on doing Semen Analysis
If neglected it may be one of the reasons for ifrtility.
Please get your semen analysis done to confirm the semen agglutination.
Please take vit c,Vit E and zinc regularly.