SHM Enterprise - Offering East India Company Half Anna Old Coins at Rs /piece in Bongaigaon, Assam. Read about company. Get contact details and. F is minimum when the coin and the platform come to rest momentarily at the one extreme position of SHM. F is maximum when the coin and the platform come to. Followers, 0 Following, Posts - See Instagram photos and videos from SHM COIN COLLECTION (@shm_coin_collection).