Hi and welcome to Just Answer!
Different expert here...and there are several issues to cover.
First of all - your basis of assets that you received as a gift is not simply the fair market value (FMV) at the time you received the gift. The basis of gifted asset is the LESSER of the fair market value (FMV) at the time you received the gift and donor's basis.
Basically - you need to determine what the donor paid for the gold - and compare with the FMV at the time you received the gift - and pick the smaller value as your basis.
To avoid confusions - you need to obtain supporting documents of donor's purchase prices.
See for reference IRS publication 551 - www.irs.gov/pub/irs-pdf/p551.pdf
- page 8 - Property Received as a Gift.
You will only recognize income and might be liable for gift taxes
- if the asset is SOLD.
As long as you keep the gifted asset - no income recognized - and no need to report anything on your tax return.
As a recipient of the gift - the person does not need to claim it as income. Regardless of the value. Please see for reference IRS publication 525 page 34 (left column)- http://www.irs.gov/pub/irs-pdf/p525.pdf
Gifts and inheritances. Generally, property you receive as a gift, bequest, or inheritance is not included in your income. However, if property you receive this way later produces income such as interest, dividends, or rents, that income is taxable to you. If property is given to a trust and the income from it is paid, credited, or distributed to you, that income is also taxable to you. If the gift, bequest, or inheritance is the income from the property, that income is taxable to you.
In additional - the large gift from non-resident aliens is reported on the form 3520 - http://www.irs.gov/pub/irs-pdf/f3520.pdf - see part IV.
There is no tax associated with this reporting. Only gifts above $100,000 are reportable.
That is assuming that all donors are nonresident aliens - in case donors are US persons - they are required to file gift tax returns.
There is no duty on gold coins, medals or bullion but these items must be declared to a Customs and Border Protection (CBP) Officer. Please keep a copy of your declaration to support the fact that gold was imported.
See for reference - https://help.cbp.gov/app/answers/detail/a_id/322/kw/gold
Please be sure you ask for clarification if needed.
Let me know if you need any help.