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Exhibit 4.1

No. INV-

                                                                        $100,000


                                 BIOCORAL, INC.

                                 March 31, 2000

                  3 Year 6 Percent Convertible Promissory Note
                             Due December 31, 2002


     BioCoral, Inc., a Delaware corporation (the "Corporation"), for value
received, promises to pay to [ ] or registered assigns, the sum of $100,000 on
December 31, 2002, and to pay interest at the rate of 6 percent per annum
annually on the last day of December of each year, computed from March 31, 2000
(the "issue date"). Payment of principal and interest shall be made at the
offices of the Corporation, either in lawful money of the United States of
America or in shares of the Corporation's common stock, at a rate determined in
accordance with Section 2(a-b) hereof, all at the Corporation's sole option.
Payment for a redeemed Note shall be mailed to the registered owner or owners
hereof at their address last appearing on the books of the Corporation.

     This note is one of a duly authorized issue of the Corporation's Notes in
the aggregate amount of at least $1,500,000, and issued in denominations or
multiples of $100,000, all of like tenor and maturity, except variations
necessary to express the number, principal amount and payee of each Note.

1.   Pari Passu. All Notes of this issue rank pari passu without priority over
     one another.

2.   Conversion.

2a.  Principal Amount. The holder or holders of this Note (subject Company
     approval and consent) may at any time, convert the principal amount of the
     note hereof into shares of the Corporation's common stock ranking pari
     passu at the conversion ratio of $0.045 of Note principal for one share of
     the Corporation's common stock. To convert this Note, the holder or holders
     hereof must surrender the same at the office of the Corporation, together
     with a written instrument of transfer in a form satisfactory to the
     Corporation, properly completed and executed and with a written notice of
     conversion.

2b.  Interest Amount. If, at any time, the Corporation, at it sole option, shall
     seek to pay interest on this Note in shares of its common stock as provided
     in the first pre-numbered paragraph of this Note the number of shares of
     the Corporation's common stock into which such






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     interest is to be converted shall be obtained by utilizing the average
     closing sale price of such shares in the over-the-counter market for the
     20 trading days immediately preceding the date such interest is due.

2c.  Adjustments to Conversion or Redemption. If the Corporation at any time
     pays to the holders of its common stock a dividend in common stock, the
     number of shares of common stock issuable upon the conversion of redemption
     of this Note shall be proportionally increased effective at the close of
     business on the record date for determination of the holders of the common
     stock entitled to the dividend.

     If the Corporation at any time subdivides or combines in a larger or
     smaller number of shares, its outstanding shares of common stock, then the
     number of shares of common stock issuable upon the conversion or redemption
     of this Note shall be proportionally increased in the case of a subdivision
     and decreased in the case of a combination, effective in either case at the
     close of business on the date that the subdivision or combination becomes
     effective, provided, however, that this provision shall not take effect
     until after the completion a maximum of first two reverse split of the
     common stock of the Corporation effected after the Issue Date.

     If the Corporation is recapitalized, consolidated with or merged into any
     other corporation, or sells or conveys to any other corporation all or
     substantially all of its property as an entity, provision shall be made as
     part of the terms of the recapitalization, consolidation, merger, sale, or
     conveyance so that the holder or holders of this Note may receive, in lieu
     of the common stock otherwise issuable to them upon conversion or
     redemption hereof, at the same conversion ratio, the same kind and amount
     of securities or assets as may be distributable upon the recapitalization,
     consolidation, merger, sale, or conveyance with respect to the common
     stock.

3.   Fractional Shares. In lieu of issuing any fraction of a share upon the
     conversion or redemption of this Note or in payment of any interest
     thereon, the Corporation shall pay to the holder hereof for any fraction of
     a share otherwise issuable a rounded-up full share.

4.   Redemption/Callability. The Corporation may, at any time, prepay in whole
     or in part the principal amount, plus accrued interest to the date of
     prepayment, of all outstanding Notes of this issue, upon 30 days' written
     notice by certified or registered mail to the registered owners of all
     outstanding Note. Such payment shall be made either in cash or in shares of
     the Corporation's common stock determined in accordance with Section 2a
     hereof for conversion of the principal amount and in accordance with
     Section 2b hereof for interest payment, in the Corporation's sole
     discretion. Such notice shall be mailed to Note holders at their addresses
     last appearing on the Corporation's books.






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5.   Registered Owner. The Corporation may treat the person or persons whose
     name or names appear on this Note as the absolute owner or owners thereof
     for the purpose of receiving payment of, or on account of, the principal
     and interest due on this Note and for all other purposes.

6.   Release of Shareholders, Officers and Directors. This Note is the
     obligation of the Corporation only, and no recourse shall be had for the
     payment of any principal or interest hereon against any shareholder,
     officer or director of the Corporation, either directly or through the
     Corporation, by virtue of any statute for the enforcement of any assessment
     or otherwise. The holder or holders of this Note, by the acceptance hereof,
     and as part of the consideration for this Note, release all claims and
     waive all liabilities against the foregoing persons in connection with the
     Note.

7.   Restricted Securities. Neither this Note nor any shares issuable upon
     conversion, redemption or payment of interest hereon, have been registered
     under the Securities Act or other state securities laws, and are being sold
     without any such registration in reliance upon the exemption from
     registration afforded by Section 4(2) of the Securities Act and
     Regulation D promulgated thereunder. As such, there will be substantial
     restrictions on its and their transferability. Each Note holder should
     consult his/her/its own counsel regarding such transferability.




                                 BIOCORAL, INC.



                                 By:
                                     -------------------------------
                                     Nasser Nassiri, Chairman





                                 By:
                                     -------------------------------
                                     Yuhko Grossmann, Director